1800+ Nouns That Start With O

Nouns are words that represent people or things. They are often the subject or object of a sentence. Nouns that start with O are some of the most interesting and unique words in the English language.

Some of the most common nouns that start with O include “object,” “operation,” and “organization.” However, there are many more unique and interesting nouns that start with this letter.

For example, the noun “ocean” represents a large body of water. The noun “octopus” represents a sea creature with eight arms. The noun “opossum” represents a North American marsupial.

As you can see, there are many different types of nouns that start with O. Each one has its own definition and meaning. Learning about these words can help you better understand the English language.

Nouns That Start With The Letter O

There are many interesting nouns that start with the letter O. Here are just a few of them:

• Oasis: A oasis is a small, green oasis in the middle of a desert.
• Oatmeal: Oatmeal is a type of porridge made from oats. It is a healthy breakfast option and can be eaten with milk, fruit, or honey.
• Ocelot: The ocelot is a small, wild cat that is found in Central and South America. They are nocturnal animals and are excellent climbers.
• Octopus: Octopuses are eight-armed sea creatures that are known for their intelligence. They are found in all the world’s oceans and are popular in many cultures as a food source.
• Odometer: An odometer is a device that is used to measure the distance traveled by a vehicle.
• Off-road: Off-road refers to driving on terrain that is not paved, such as dirt roads or trails.
• Ogre: An ogre is a mythical creature that is often described as being large and ugly.
• Ohm: The ohm is the unit of measurement for electrical resistance.
• Oil: Oil is a type of fossil fuel that is used to power many vehicles and machines.
• Olympics: The Olympics are a series of international sporting events that are held every four years.
• Opera: Opera is a type of musical theatre that originated in Italy in the 16th century.
• Orange: The orange is a type of fruit that is named for its orange color. It is a popular citrus fruit that is used in many recipes.
• Orchestra: An orchestra is a large group of musicians who play together. They are often seen in symphony halls and opera houses.
• Organ: An organ is a musical instrument that is played using a keyboard. Organs are often used in churches and cathedrals.
• Ostrich: The ostrich is a large bird that is native to Africa. They are the largest bird in the world and can run up to speeds of 40 miles per hour.
• Otter: Otters are small, aquatic mammals that are found in many parts of the world. They are known for their playful nature and their thick fur.

31 Nouns That Start With OA

Oahu	The third largest of the Hawaiian islands; population 905,000 (est. 2008). Its principal town, Honolulu, is the capital of Hawaii. It is the site of Pearl Harbor, a US naval base.
Oakham	town in Leicestershire in east central England that was the capital of the former county of Rutlandshire population11000
Oakland	An industrial port in California, on the eastern side of San Francisco Bay; population 404,155 (est. 2008).
Oakley	city in California northeast of Oaklandpopulation35432
Oates	Joyce Carol 1938– American writerTitus 1649–1705 British fabricator of the Popish Plot
Oaxaca	A state of southern Mexico.
oaf	A stupid, uncultured, or clumsy person.
oafs	A stupid, uncultured, or clumsy person.
oak	A tree that bears acorns as fruit, and typically has lobed deciduous leaves. Oaks are common in many north temperate forests and are an important source of hard and durable wood used chiefly in construction, furniture, and (formerly) shipbuilding.
oaks	A tree that bears acorns as fruit, and typically has lobed deciduous leaves. Oaks are common in many north temperate forests and are an important source of hard and durable wood used chiefly in construction, furniture, and (formerly) shipbuilding.
oakum	Loose fiber obtained by untwisting old rope, used especially in caulking wooden ships.
oar	A pole with a flat blade, pivoting in an oar lock, used to row or steer a boat through the water. Row; propel with or as with oars.
oars	A pole with a flat blade, pivoting in an oar lock, used to row or steer a boat through the water. Row; propel with or as with oars.
oarsman	A rower, especially as a member of a racing team.
oarsmanship	one who rows especially in a racing crew
oarswoman	A female rower, especially as a member of a racing team.
oasis	A fertile spot in a desert, where water is found.
oast	A kiln used for drying hops.
oast-house	a usually conical kiln used for drying hops, malt, or tobacco
oast-houses	a usually conical kiln used for drying hops, malt, or tobacco
oasts	A kiln used for drying hops.
oat	A cereal plant cultivated chiefly in cool climates and widely used for animal feed as well as human consumption.
oatcake	A thin, unleavened cake made of oatmeal.
oatcakes	A thin, unleavened cake made of oatmeal.
oater	A western movie or television show.
oaters	A western movie or television show.
oath	A solemn promise, often invoking a divine witness, regarding one’s future action or behavior. A coarse or blasphemous word or phrase used to express anger or other strong emotion.
oaths	A solemn promise, often invoking a divine witness, regarding one’s future action or behavior. A coarse or blasphemous word or phrase used to express anger or other strong emotion.
oatmeal	Meal made from ground oats, used in breakfast cereals or other food. A grayish-beige color flecked with brown.
oatmeals	meal made from oats
oats	A cereal plant cultivated chiefly in cool climates and widely used for animal feed as well as human consumption.

172 Nouns Starting With OB

Obadiah	(in the Bible) a Hebrew minor prophet.
obeah	A kind of sorcery practiced especially in the Caribbean.
obeche	A tropical tree native to West and central Africa, grown for its pale timber which is used for plywood and veneers.
obelisk	A stone pillar, typically having a square or rectangular cross section and a pyramidal top, set up as a monument or landmark.
obelus	A symbol (†) used as a reference mark in printed matter, or to indicate that a person is deceased. A mark (– or ÷) used in ancient texts to mark a word or passage as spurious, corrupt, or doubtful.
obesity	The state or condition of being very fat or overweight.
obiism	The practice of obeah; belief in obeah.
obis	A broad sash worn around the waist of a Japanese kimono.
obits	An obituary.
object	A material thing that can be seen and touched. A person or thing to which a specified action or feeling is directed. Grammar Computing Say something to express one’s disapproval of or disagreement with something.
objects	A material thing that can be seen and touched. A person or thing to which a specified action or feeling is directed. Grammar Computing Say something to express one’s disapproval of or disagreement with something.
oblast	An administrative division or region in Russia and the former Soviet Union, and in some of its former constituent republics.
oblasts	An administrative division or region in Russia and the former Soviet Union, and in some of its former constituent republics.
oblate	(of a spheroid) flattened at the poles. A person dedicated to a religious life, but typically having not taken full monastic vows.
oblong	An object or flat figure in an elongated rectangle or oval shape. Having an elongated shape, as a rectangle or an oval.
oboes	A woodwind instrument with a double-reed mouthpiece, a slender tubular body, and holes stopped by keys.
obolus	History (In form Obolus) a genus of fossil brachiopods having a smooth orbicular shell, widespread in Cambrian and Ordovician rocks; (also obolus) a brachiopod of this genus.
obs	Denoting exposure or openness. Denoting opposition, hostility, or resistance. Denoting extensiveness, finality, or completeness. (in modern technical words) inversely; in a direction or manner contrary to the usual.
obtund	Dull the sensitivity of; blunt; deaden.

Oban	Oberammergau	Oberhausen
Oberland	Oberon	oba
obas	obbligato	obbligatos
obduracy	obeahism	obeahs
obeches	obedience	obedientiaries
obedientiary	obeisance	obeisances
obelisks	obeyer	obeyers
obfuscation	obfuscations	obi
obit	obituaries	obituary
objectification	objection	objections
objective	objectiveness	objectives
objectivism	objectivist	objectivists
objectivities	objectivity	objector
objectors	objurgation	objurgations
oblateness	oblates	oblation
oblations	obligation	obligations
obligato	obligatoriness	obligatos
obligee	obligees	obligingness
obligor	obligors	oblique
obliqueness	obliques	obliquities
obliquity	obliteration	obliterations
oblivion	oblivions	obliviousness
oblongs	obloquies	obloquy
obmutescence	obnoxiousness	oboe
oboist	oboists	obreption
obscenities	obscenity	obscurant
obscurantism	obscurantist	obscurantists
obscurants	obscuration	obscurations
obscure	obscureness	obscures
obscurities	obscurity	obsecration

obsecrations	obsequiousness	observableness
observance	observances	observation
observations	observatories	observatory
observer	observers	obsession
obsessions	obsessiveness	obsidian
obsolescence	obsoleteness	obstacle
obstacles	obstetrician	obstetricians
obstetrics	obstinacy	obstinateness
obstipation	obstipations	obstreperousness
obstruct	obstructer	obstructers
obstruction	obstructionism	obstructionist
obstructionists	obstructions	obstructiveness
obstructor	obstructors	obstructs
obstruent	obstruents	obtainment
obtention	obtentions	obtestation
obtestations	obtruder	obtruders
obtrusiveness	obtunds	obturation
obturator	obturators	obtuseness
obumbration	obumbrations	obverse
obverses	obversion	obversions
obviation	obviations	obviousness

142 Words That Start With OC Nouns

Oceania	An area that encompasses the islands of the Pacific Ocean and adjacent seas.
Oceanus	The son of Uranus (Heaven) and Gaia (Earth), the personification of the great river believed to encircle the whole world.
Ockham	(c. 1285–1349), English philosopher and Franciscan friar. A defender of nominalism, he is known for the maxim called “Occam’s razor. ”.
Octans	A faint southern constellation (the Octant), containing the south celestial pole. postpositive
October	The tenth month of the year, in the northern hemisphere usually considered the second month of autumn.
oca	A South American plant related to wood sorrel, long cultivated in Peru for its edible tubers.
ocarina	A small egg-shaped wind instrument with a mouthpiece and holes for the fingers.
occults	Supernatural, mystical, or magical beliefs, practices, or phenomena. Of, involving, or relating to supernatural, mystical, or magical powers or phenomena. Medicine Cut off from view by interposing something.
ocean	A very large expanse of sea, in particular each of the main areas into which the sea is divided geographically.
oceanic	Relating to the ocean.
oceanid	A sea nymph; one of the daughters of Oceanus.
oceans	A very large expanse of sea, in particular each of the main areas into which the sea is divided geographically.
ocelot	A medium-sized wild cat that has a tawny yellow coat marked with black blotches and spots, and ranges from southern Texas through South America.
ocelots	A medium-sized wild cat that has a tawny yellow coat marked with black blotches and spots, and ranges from southern Texas through South America.
ocher	An earthy pigment containing ferric oxide, typically with clay, varying from light yellow to brown or red.
ochre	An earthy pigment containing ferric oxide, typically with clay, varying from light yellow to brown or red.
ocker	A boorish or aggressive person, especially an Australian man.
ockers	A boorish or aggressive person, especially an Australian man.
ocrea	A dry sheath around a stem formed by the cohesion of two or more stipules, characteristic of the dock family.
octads	A group or set of eight.
octagon	A plane figure with eight straight sides and eight angles.
octal	Relating to or using a system of numerical notation that has 8 rather than 10 as a base. The octal system; octal notation.
octane	A colorless flammable hydrocarbon of the alkane series, obtained in petroleum refining.
octant	An arc of a circle equal to one eighth of its circumference, or the area enclosed by such an arc with two radii of the circle.
octants	An arc of a circle equal to one eighth of its circumference, or the area enclosed by such an arc with two radii of the circle.
octave	Music A poem or stanza of eight lines; an octet. The eighth day after a church festival, inclusive of the day of the festival. Fencing
octaves	Music A poem or stanza of eight lines; an octet. The eighth day after a church festival, inclusive of the day of the festival. Fencing
octavo	A size of book page that results from folding each printed sheet into eight leaves (sixteen pages)
octavos	A size of book page that results from folding each printed sheet into eight leaves (sixteen pages)
octet	A group of eight people or things.
octets	A group of eight people or things.
octette	A group of eight people or things.
octopod	A cephalopod mollusk of the order Octopoda; an octopus.
ocular	Of or connected with the eyes or vision.
oculus	A round or eye-like opening or design, such as a circular window or an opening at the apex of a dome.

Occam	Occamism	Occamist
Occidentalism	Occidentalist	Oceanian
Octavia	Octavian	Octobrist
ocarinas	ocas	occasion
occasionalism	occasionality	occasions
occident	occidental	occidentals
occipital	occipitals	occiput
occiputs	occlusion	occlusions
occlusive	occlusives	occult
occultation	occultations	occultism
occultist	occultists	occultness
occupancies	occupancy	occupant
occupants	occupation	occupations
occupier	occupiers	occupying
occurrence	occurrences	oceanarium
oceanariums	oceanides	oceanids
oceanographer	oceanographers	oceanography
oceanology	ocellation	ocellations
ocellus	ochlocracy	ochlocrat
ochlocrats	ochlophobia	ochrea
ochres	ocotillo	ocotillos
octachord	octachords	octad
octagons	octahedrite	octahedron
octahedrons	octameter	octameters
octanes	octaroon	octaroons
octettes	octillion	octillions
octillionth	octillionths	octocentenaries
octocentenary	octodecimo	octodecimos
octogenarian	octogenarians	octonaries
octonary	octopodes	octopods

octopus	octopuses	octoroon
octoroons	octosyllable	octosyllables
octroi	octrois	octuple
octuples	octuplet	octuplets
ocularist	oculars	oculist
oculists	oculomotor

55 Nouns Beginning With OD

Oder	A river of central Europe that rises in the mountains in western Czech Republic, flows north through western Poland to meet the Neisse River, and then continues north to form the northern part of the border between Poland and Germany before flowing into the Baltic Sea.
Odessa	A city and port on the southern coast of Ukraine, on the Black Sea; population 1,008,600 (est. 2009). Ukrainian name Odesa. A city in southwestern Texas, an oil industry center (with its neighbor Midland) in the Permian Basin; population 98,801 (est. 2008).
Odin	the supreme god and creator in Norse mythology
Odinism	The worship of Odin, the supreme god and creator in Scandinavian mythology; the mythology and religious doctrine of the ancient Scandinavians, before the introduction of Christianity.
Odysseus	The king of Ithaca and central figure of the Odyssey, renowned for his cunning and resourcefulness.
odalisque	A female slave or concubine in a harem, especially one in the seraglio of the Sultan of Turkey.
odalisques	A female slave or concubine in a harem, especially one in the seraglio of the Sultan of Turkey.
odd	Different from what is usual or expected; strange. (of whole numbers such as 3 and 5) having one left over as a remainder when divided by two. attributiveSeparated from a usual pair or set and therefore out of place or mismatched.
oddball	A strange or eccentric person. Strange; bizarre.
oddballs	A strange or eccentric person. Strange; bizarre.
oddities	A strange or peculiar person, thing, or trait.
oddity	A strange or peculiar person, thing, or trait.
oddment	A remnant or part of something, typically left over from a larger piece or set.
odds	the probability that one thing is so or will happen rather than another
ode	A lyric poem in the form of an address to a particular subject, often elevated in style or manner and written in varied or irregular meter.
odes	A lyric poem in the form of an address to a particular subject, often elevated in style or manner and written in varied or irregular meter.
odeums	(especially in ancient Greece or Rome) a building used for musical performances.
odiousness	arousing or deserving hatred or repugnance
odium	General or widespread hatred or disgust directed toward someone as a result of their actions.
odometer	An instrument for measuring the distance traveled by a vehicle.
odometers	An instrument for measuring the distance traveled by a vehicle.
odometry	Measurement by an odometer of distances travelled.
odontoblast	A cell in the pulp of a tooth that produces dentin.
odontograph	An instrument for marking or setting out the teeth of gearwheels so that they mesh accurately.
odontolite	Fossil tooth or bone coloured blue by mineral impregnation; bone turquoise.
odontology	The scientific study of the structure and diseases of teeth.
odor	A distinctive smell, especially an unpleasant one. A lingering quality, impression, or feeling attaching to something.
odoriferousness	The quality or condition of being odoriferous; fragrance.
odyl	a force or natural power formerly held by some to reside in certain individuals and things and to underlie hypnotism and magnetism and some other phenomena
odyles	Od.
odyssey	A long and eventful or adventurous journey or experience. A Greek hexameter epic poem traditionally ascribed to Homer, describing the travels of Odysseus during his ten years of wandering after the fall of Troy. He eventually returned home to Ithaca and killed the suitors who had plagued his wife Penelope during his absence.
odysseys	A long and eventful or adventurous journey or experience. A Greek hexameter epic poem traditionally ascribed to Homer, describing the travels of Odysseus during his ten years of wandering after the fall of Troy. He eventually returned home to Ithaca and killed the suitors who had plagued his wife Penelope during his absence.

Odelsting	Odense	Odette
Odinist	Odinists	odd-jobman
oddments	oddness	odeum
odiums	odontalgia	odontoblasts
odontogeny	odontoglossum	odontoglossums
odontographs	odontography	odontolites
odontophore	odontophorus	odour
odours	odylism

26 Nouns That Start With OE

Oedipus	The son of Jocasta and of Laius, king of Thebes.
Oenone	A nymph of Mount Ida and lover of Paris, who deserted her for Helen.
oedema	A condition characterized by an excess of watery fluid collecting in the cavities or tissues of the body.
oeil-de-boeuf	A small round window.
oeillade	A glance of the eye; a meaningful or knowing look, especially an amorous look, an ogle.
oeillades	A glance of the eye; a meaningful or knowing look, especially an amorous look, an ogle.
oenologist	a science that deals with wine and wine making
oenologists	a science that deals with wine and wine making
oenology	The study of wines.
oenomel	Something (especially thought, language, etc. ) in which strength and sweetness are combined.
oenophile	A connoisseur of wines.
oenophiles	A connoisseur of wines.
oersted	A unit of magnetic field strength equivalent to 79. 58 amperes per meter.
oersteds	A unit of magnetic field strength equivalent to 79. 58 amperes per meter.
oesophagus	The part of the alimentary canal that connects the throat to the stomach; the gullet. In humans and other vertebrates it is a muscular tube lined with mucous membrane.
oestradiol	A major estrogen produced in the ovaries.
oestrogen	Any of a group of steroid hormones which promote the development and maintenance of female characteristics of the body. Such hormones are also produced artificially for use in oral contraceptives or to treat menopausal and menstrual disorders.
oestrogens	any of various natural steroids (such as estradiol) that are formed from androgen precursors, that are secreted chiefly by the ovaries, placenta, adipose tissue, and testes, and that stimulate the development of female secondary sex characteristics and promote the growth and maintenance of the female reproductive system
oestrus	A recurring period of sexual receptivity and fertility in many female mammals; heat.
oestruses	a regularly recurrent state of sexual receptivity during which the female of most mammals will accept the male and is capable of conceiving
oeuvre	The works of a painter, composer, or author regarded collectively.
oeuvres	The works of a painter, composer, or author regarded collectively.

oecology	oedemas	oenophilist
oenophilists

67 Nouns Starting With OF

Offa	Off. (died 796), king of Mercia 757–796. He organized the construction of Offa’s Dyke, a series of earthworks marking the traditional boundary between England and Wales.
Offaly	A county in the central part of the Republic of Ireland, in the province of Leinster; county town, Tullamore.
Offenbach	Jacques 1819–1880 originally Jacob Eberst French composercity in southwest central Germany on the Main River east of Frankfurt am Mainpopulation113500
off	Away from the place in question; to or at a distance. So as to be removed or separated. Starting a journey or race; leaving. So as to bring to an end or be discontinued. (of an electrical appliance or power supply) not functioning or so as to cease to function. Having access to or possession of material goods or wealth to the extent specified. Moving away and often down from. Situated or leading in a direction away from (a main route or intersection)So as to be removed or separated from. attributivepredicativeattributiveBritish The half of the field (as divided lengthways through the pitch) toward which the batsman’s feet are pointed when standing to receive the ball. Kill; murder.
off-day	A day’s vacation from work or school on what would normally be a working day.
off-days	A day’s vacation from work or school on what would normally be a working day.
off-licence	British
off-white	A white color with a gray or yellowish tinge.
offal	The entrails and internal organs of an animal used as food.
offals	The entrails and internal organs of an animal used as food.
offbeat	Unconventional; unusual. Music Any of the normally unaccented beats in a bar.
offence	A breach of a law or rule; an illegal act. Annoyance or resentment brought about by a perceived insult to or disregard for oneself or one’s standards or principles. The action of attacking someone or something.
offences	something that outrages the moral or physical senses
offender	A person who commits an illegal act. A person or thing that offends, does something wrong, or causes problems.
offenders	A person who commits an illegal act. A person or thing that offends, does something wrong, or causes problems.
offense	A breach of a law or rule; an illegal act. Annoyance or resentment brought about by a perceived insult to or disregard for oneself or one’s standards or principles. The action of attacking someone or something.
offenses	something that outrages the moral or physical senses
offensive	Causing someone to feel deeply hurt, upset, or angry. attributiveAn attacking military campaign.
offensives	Causing someone to feel deeply hurt, upset, or angry. attributiveAn attacking military campaign.
offer	Present or proffer (something) for (someone) to accept or reject as so desired. An expression of readiness to do or give something if desired.
offerer	one that offers
offerers	one that offers
offering	A thing offered, especially as a gift or contribution.
offerings	A thing offered, especially as a gift or contribution.
offeror	one that offers
offerors	one that offers
offers	Present or proffer (something) for (someone) to accept or reject as so desired. An expression of readiness to do or give something if desired.
offertories	Christian Church Christian Church
offertory	Christian Church Christian Church
office	A room, set of rooms, or building used as a place for commercial, professional, or bureaucratic work. A position of authority or service, typically one of a public nature. usually offices
officer	A person holding a position of command or authority in the armed services, in the merchant marine, or on a passenger ship. A holder of a public, civil, or ecclesiastical office. A member of a certain grade in some honorary orders. Provide with military officers.
officers	A person holding a position of command or authority in the armed services, in the merchant marine, or on a passenger ship. A holder of a public, civil, or ecclesiastical office. A member of a certain grade in some honorary orders. Provide with military officers.
offices	A room, set of rooms, or building used as a place for commercial, professional, or bureaucratic work. A position of authority or service, typically one of a public nature. usually offices
official	Relating to an authority or public body and its duties, actions, and responsibilities. A person holding public office or having official duties, especially as a representative of an organization or government department.
officialdom	The officials in an organization or government department, considered as a group.
officialese	The formal and typically verbose style of writing considered to be characteristic of official documents, especially when it is difficult to understand.
officials	Relating to an authority or public body and its duties, actions, and responsibilities. A person holding public office or having official duties, especially as a representative of an organization or government department.
officiant	A person, typically a priest or minister, who performs a religious service or ceremony.
officiants	A person, typically a priest or minister, who performs a religious service or ceremony.
officiating	Act as an official in charge of something, as a sporting event.
officiator	one that officiates
officinal	(of a herb or drug) standardly used in medicine.
offing	The more distant part of the sea in view.
offings	The more distant part of the sea in view.
offishness	standoffish
offprint	A printed copy of an article that originally appeared as part of a larger publication.
offprints	A printed copy of an article that originally appeared as part of a larger publication.
offs	Away from the place in question; to or at a distance. So as to be removed or separated. Starting a journey or race; leaving. So as to bring to an end or be discontinued. (of an electrical appliance or power supply) not functioning or so as to cease to function. Having access to or possession of material goods or wealth to the extent specified. Moving away and often down from. Situated or leading in a direction away from (a main route or intersection)So as to be removed or separated from. attributivepredicativeattributiveBritish The half of the field (as divided lengthways through the pitch) toward which the batsman’s feet are pointed when standing to receive the ball. Kill; murder.
offset	A consideration or amount that diminishes or balances the effect of a contrary one. The amount or distance by which something is out of line. A side shoot from a plant serving for propagation. Architecture A bend in a pipe to carry it past an obstacle. often as modifierwith objectwith objectno object
offsets	A consideration or amount that diminishes or balances the effect of a contrary one. The amount or distance by which something is out of line. A side shoot from a plant serving for propagation. Architecture A bend in a pipe to carry it past an obstacle. often as modifierwith objectwith objectno object
offshoot	A side shoot or branch on a plant.
offshoots	A side shoot or branch on a plant.
offside	(especially in soccer or hockey) in a position where playing the ball or puck is not allowed, especially (in soccer) in the attacking half ahead of the ball and having fewer than two defenders nearer the goal line at the moment the ball is played. (especially in soccer or hockey) occupying or taking place in a position where playing the ball or puck is not allowed, especially (in soccer) in the attacking half ahead of the ball and having fewer than two defenders nearer the goal line at the moment the ball is played. The fact of being offside in soccer and other sports. usually the off side
offsider	helper, assistant, associate, follower
offspring	A person’s child or children.
offsprings	the product of the reproductive processes of a person, animal, or plant
offtake	the act of taking off
offtakes	the act of taking off
oftenness	The fact or condition of occurring often; frequency.

off-licences	offensiveness	office-bearer
office-bearers	officialisms	officiators
officiousness

21 Words That Start With OG Nouns

Ogaden	A desert region in southeastern Ethiopia, largely inhabited by Somali nomads. It has been claimed by successive governments of neighboring Somalia.
Ogbomosho	A city and agricultural market in southwestern Nigeria, north of Ibadan; population 951,000 (est. 2007).
Ogpu	An organization for investigating and combating counterrevolutionary activities in the former Soviet Union, existing from 1922 (1922–3 as the GPU) to 1934 and replacing the Cheka. It was absorbed into the NKVD in 1934.
ogam	An ancient British and Irish alphabet, consisting of twenty characters formed by parallel strokes on either side of or across a continuous line.
ogams	An ancient British and Irish alphabet, consisting of twenty characters formed by parallel strokes on either side of or across a continuous line.
ogdoad	A group or set of eight.
ogdoads	A group or set of eight.
ogee	Having a double continuous S-shaped curve. An S-shaped line or molding.
ogees	Having a double continuous S-shaped curve. An S-shaped line or molding.
ogham	An ancient British and Irish alphabet, consisting of twenty characters formed by parallel strokes on either side of or across a continuous line.
oghams	An ancient British and Irish alphabet, consisting of twenty characters formed by parallel strokes on either side of or across a continuous line.
ogive	Architecture Statistics
ogives	Architecture Statistics
ogle	Stare at in a lecherous manner. A lecherous look.
ogler	to glance with amorous invitation or challenge
oglers	to glance with amorous invitation or challenge
ogles	Stare at in a lecherous manner. A lecherous look.
ogre	(in folklore) a man-eating giant.
ogres	(in folklore) a man-eating giant.
ogress	A female ogre.
ogresses	A female ogre.

6 Nouns Beginning With OH

Ohio	A state in the northeastern US, bordering on Lake Erie; population 11,485,910 (est. 2008); capital, Columbus. Acquired by Britain from France in 1763 and by the US in 1783, it became the 17th state of the US in 1803.
ohm	The SI unit of electrical resistance, expressing the resistance in a circuit transmitting a current of one ampere when subjected to a potential difference of one volt.
ohmage	Electrical resistance as expressed in ohms.
ohmmeter	An instrument for measuring electrical resistance.
ohmmeters	An instrument for measuring electrical resistance.
ohms	On Her (or His) Majesty’s Service.

24 Nouns That Start With OI

Oise	river 188 miles (302 kilometers) long in northern France flowing southwest into the Seine River
Oistrakh	David Fyodorovich 1908–1974 Russian violinist
oidium	Botany A fungal disease affecting vines, caused by a powdery mildew.
oik	An uncouth or obnoxious person.
oiks	An uncouth or obnoxious person.
oil	A viscous liquid derived from petroleum, especially for use as a fuel or lubricant. often oilsLubricate, coat, or impregnate with oil. Supply with oil as fuel.
oilcan	A can containing lubricating oil, especially one with a long nozzle.
oilcans	A can containing lubricating oil, especially one with a long nozzle.
oilcloth	Fabric treated on one side with oil to make it waterproof.
oilcloths	Fabric treated on one side with oil to make it waterproof.
oiler	An oil tanker. A person who oils machinery. oilers
oilers	An oil tanker. A person who oils machinery. oilers
oiliness	of, relating to, or consisting of oil
oilman	An owner or employee of an oil company.
oilpaper	Paper made transparent or waterproof by treatment with oil.
oils	A viscous liquid derived from petroleum, especially for use as a fuel or lubricant. often oilsLubricate, coat, or impregnate with oil. Supply with oil as fuel.
oilskin	Heavy cotton cloth waterproofed with oil.
oilskins	an oiled waterproof cloth used for coverings and garments
oilstone	A fine-grained flat stone used with oil for sharpening cutting edges.
oilstones	A fine-grained flat stone used with oil for sharpening cutting edges.
ointment	A smooth oily preparation that is rubbed on the skin for medicinal purposes or as a cosmetic.
ointments	A smooth oily preparation that is rubbed on the skin for medicinal purposes or as a cosmetic.
oiticica	Any of several tropical South American trees, especially Licania rigida (family Chrysobalanaceae), whose crushed seeds yield a drying oil used in paints and varnishes.
oiticicas	Any of several tropical South American trees, especially Licania rigida (family Chrysobalanaceae), whose crushed seeds yield a drying oil used in paints and varnishes.

2 Nouns Starting With OJ

Ojibwa	A member of a North American people of the region around Lake Superior. The Algonquian language of the Ojibwa. Relating to the Ojibwa or their language.
Ojibwas	A member of a North American people of the region around Lake Superior. The Algonquian language of the Ojibwa. Relating to the Ojibwa or their language.

14 Words That Start With OK Nouns

Okavango	A river in southwestern Africa that rises in central Angola and flows 1,000 miles (1,600 km) south and then east to Namibia, where it turns east to form part of the border between Angola and Namibia before entering Botswana, where it drains into the extensive Okavango marshes.
Okayama	An industrial city and major railway junction in southwestern Japan, on the southwestern coast of the island of Honshu; population 683,258 (2007).
Okinawa	An island in southern Japan, the largest of the Ryukyu Islands; chief town, Naha. An important World War II battle here in 1945 allowed the victorious Allies to establish bases close to the Japanese mainland.
Oklahoma	A state in the southern central US, north of Texas; population 3,642,361 (est. 2008); capital, Oklahoma City. Acquired from the French as part of the Louisiana Purchase in 1803, it became the 46th state of the US in 1907.
oka	An Egyptian and former Turkish unit of weight, variable but now usually equal to approximately 1. 3 kg (23/4 lb). An Egyptian and former Turkish unit of capacity equal to approximately 0. 2 liter (1/3 pint).
okapi	A large browsing mammal of the giraffe family that lives in the rainforests of northern Democratic Republic of Congo (Zaire). It has a dark chestnut coat with stripes on the hindquarters and upper legs.
okapis	A large browsing mammal of the giraffe family that lives in the rainforests of northern Democratic Republic of Congo (Zaire). It has a dark chestnut coat with stripes on the hindquarters and upper legs.
okas	An Egyptian and former Turkish unit of weight, variable but now usually equal to approximately 1. 3 kg (23/4 lb). An Egyptian and former Turkish unit of capacity equal to approximately 0. 2 liter (1/3 pint).
okay	Used to express assent, agreement, or acceptance. Satisfactory but not exceptionally or especially good. In a satisfactory manner or to a satisfactory extent. An authorization or approval. Sanction or give approval to. Oklahoma (in official postal use).
okays	Used to express assent, agreement, or acceptance. Satisfactory but not exceptionally or especially good. In a satisfactory manner or to a satisfactory extent. An authorization or approval. Sanction or give approval to. Oklahoma (in official postal use).
oke	South African
okes	South African
okra	A plant of the mallow family with long ridged seedpods, native to the Old World tropics.
okras	a tall annual herb (Abelmoschus esculentus) of the mallow family that is cultivated for its mucilaginous green pods used especially in soups or stews

82 Nouns Beginning With OL

Olaf	The name of five kings of Norway.
Oligochaeta	a class or in former classifications an order of Chaetopoda comprising hermaphroditic terrestrial and aquatic annelids distinguished from the polychaetes by possession of compact localized gonads and simple direct life histories without formation of a trochophore and by lack of parapodia and head specialization — see archioligochaeta , neoligochaeta
oldie	An old song, film, or television program that is still well known or popular.
olds	An Oldsmobile car, especially a large family saloon model.
oligarchs	A ruler in an oligarchy. (especially in Russia) a very rich business leader with a great deal of political influence.
olio	A highly spiced stew of various meats and vegetables originating from Spain and Portugal. A miscellaneous collection of things.
olla	A palm leaf, especially a leaf or strip of a leaf of the palmyra, traditionally used in Southern India and Sri Lanka for writing on.

Oldenburg	Oldham	Olea
Olga	Oligocene	Olivia
Olivier	Ollie	Olwen
Olympia	Olympiad	Olympiads
Olympian	Olympians	Olympus
old	old-fashioned	old-fashionedness
old-timer	old-timers	oldies
oldness	oldster	oldsters
oleaginousness	oleander	oleanders
olearia	olearias	oleaster
oleasters	oleate	oleates
olecranon	olecranons	olefin
olefine	olefines	olefins
oleins	oleo	oleograph
oleographs	oleography	oleomargarine
oleos	oleum	olfaction
olfactory	olibanum	oligarch
oligarchies	oligarchy	oligochaete
oligochaetes	oligoclase	oligopolies
oligopoly	oligopsonies	oligopsony
oliguria	olios	olive
olivenite	olives	olivine
olla-podrida	ollas	olm
olms	ology	oloroso
olorosos	olympics

51 Nouns That Start With OM

Omagh	district of western Northern Ireland, established in 1974 area 436 square miles (1134 square kilometers), population51000town in central Omagh district of western Northern Ireland population19000
Omaha	A city in eastern Nebraska, on the Missouri River; population 438,646 (est. 2008). A member of a North American people of northeastern Nebraska. The Siouan language of the Omaha. Relating to the Omaha or their language.
Oman	A country at the eastern corner of the Arabian peninsula; population 4,500,000 (estimated 2015); capital, Muscat; language, Arabic (official).
Omar	rubaiyat stanza
Omayyad	A member of a Muslim dynasty that ruled the Islamic world from AD 660 (or 661) to 750 and Moorish Spain from 756 to 1031. The dynasty claimed descent from Umayya, a distant relative of Muhammad. Relating to the Umayyad dynasty.
Omdurman	A city in central Sudan, on the Nile River opposite Khartoum; population 3,151,600 (est. 2007).
Omsk	A city in south central Russia, on the Irtysh River; population 1,131,100 (est. 2008).
omadhaun	fool, idiot, simpleton
omadhauns	fool, idiot, simpleton
omasum	The muscular third stomach of a ruminant animal, between the reticulum and the abomasum.
ombre	A trick-taking card game for three people using a pack of forty cards, popular in Europe in the 17th–18th centuries. Having tones of color that shade into each other, graduating from light to dark.
ombu	A large evergreen tree, Phytolacca dioica (family Phytolaccaceae), having a thick trunk with spreading buttresses at its base, native to South America and planted elsewhere as a shade tree. Also “ombú tree”.
ombudsman	An official appointed to investigate individuals’ complaints against maladministration, especially that of public authorities.
ombus	a large herbaceous South American tree (Phytolacca dioica) having an immensely broad trunk, soft spongy wood, and dark green oval leaves
omega	The twenty-fourth, and last, letter of the Greek alphabet (Ω, ω), transliterated as ‘o’ or ‘ō. ’. Ohm(s)
omegas	The twenty-fourth, and last, letter of the Greek alphabet (Ω, ω), transliterated as ‘o’ or ‘ō. ’. Ohm(s)
omelet	A dish of beaten eggs cooked in a frying pan until firm, often with a filling added while cooking, and usually served folded over.
omelets	beaten eggs cooked without stirring until set and served folded in half
omelette	A dish of beaten eggs cooked in a frying pan until firm, often with a filling added while cooking, and usually served folded over.
omelettes	beaten eggs cooked without stirring until set and served folded in half
omen	An event regarded as a portent of good or evil.
omens	An event regarded as a portent of good or evil.
omentum	A fold of peritoneum connecting the stomach with other abdominal organs.
omer	An ancient Hebrew dry measure, the tenth part of an ephah. Omer
omers	An ancient Hebrew dry measure, the tenth part of an ephah. Omer
omicron	The fifteenth letter of the Greek alphabet (Ο, ο), transliterated as ‘o. ’.
omicrons	The fifteenth letter of the Greek alphabet (Ο, ο), transliterated as ‘o. ’.
omission	A person or thing that has been left out or excluded.
omissions	A person or thing that has been left out or excluded.
ommatidium	Each of the optical units that make up a compound eye, as of an insect.
ommatophore	A part of an invertebrate animal, especially a stalk or tentacle, that bears an eye.
ommatophores	A part of an invertebrate animal, especially a stalk or tentacle, that bears an eye.
omnibus	A volume containing several novels or other items previously published separately. dated Comprising several items.
omnibuses	A volume containing several novels or other items previously published separately. dated Comprising several items.
omnipotence	The quality of having unlimited or very great power.
omnipotences	The quality of having unlimited or very great power.
omnipotent	(of a deity) having unlimited power; able to do anything. God.
omnipresence	The state of being widespread or constantly encountered.
omniscience	The state of knowing everything.
omnium-gatherum	A collection of miscellaneous people or things.
omnivore	An animal or person that eats food of both plant and animal origin.
omnivores	An animal or person that eats food of both plant and animal origin.
omnivorousness	feeding on both animal and vegetable substances
omophagia	The eating of raw food, especially raw meat.
omophorion	A vestment worn by patriarchs and bishops, corresponding to and resembling the pallium of the Latin Church.
omophorions	A vestment worn by patriarchs and bishops, corresponding to and resembling the pallium of the Latin Church.
omphalos	literary

Omayyads	omber	ominousness
omphaloses

80 Nouns Starting With ON

Oneida	A member of an Iroquoian people formerly inhabiting upper New York State, one of the five peoples comprising the original Iroquois confederacy. The Iroquoian language of the Oneida. Relating to the Oneida or their language.
onager	An animal of a race of the Asian wild ass native to northern Iran.
oncogene	a gene having the potential to cause a normal cell to become cancerous
oncologist	A medical practitioner qualified to diagnose and treat tumors.
oner	A remarkable person or thing.
ones	Referring to a person or thing previously mentioned or easily identified. A person of a specified kind. third person singular
onions	An edible bulb with a pungent taste and smell, composed of several concentric layers, used in cooking. The plant that produces the onion, with long rolled or straplike leaves and spherical heads of greenish-white flowers.
onrush	A surging rush forward.
onset	The beginning of something, especially something unpleasant.
onsets	The beginning of something, especially something unpleasant.

Onassis	Oneidas	Onondaga
Onondagas	Ontario	onagers
onanism	onanist	onanists
once	once-over	oncer
oncers	onchocerciasis	oncidium
oncidiums	oncogenes	oncologists
oncology	oncoming	oncomings
oncost	oncosts	ondatra
ondatras	ondine	ondines
onding	ondings	one
one-acter	one-liner	one-liners
one-nighter	one-nighters	one-off
one-offs	one-sidedness	one-step
one-steps	one-two	one-upmanship
oneirocritic	oneirocriticism	oneiromancy
oneness	onerousness	oners
onion	onlooker	onlookers
onomasticon	onomasticons	onomastics
onomatopoeia	onomatopoeias	onrushes
onslaught	onslaughts	ontogenesis
ontogeny	ontologist	ontologists
ontology	onus	onuses
onychia	onychium	onyx
onyxes

40 Words That Start With OO Nouns

oocyte	A cell in an ovary which may undergo meiotic division to form an ovum.
oodles	A very great number or amount of something.
oolite	Geology
oology	The study or collecting of birds’ eggs.
oolong	A dark-colored China tea made by fermenting the withered leaves to about half the degree usual for black teas.
oompah	Used to refer to the rhythmical sound of deep-toned brass instruments in a band. Make an ‘oompah’
oomph	The quality of being exciting, energetic, or sexually attractive.
oose	Fluff from wool, cotton, etc.
ooses	Fluff from wool, cotton, etc.

Oona	Oonagh	Oostende
oocytes	oof	oofs
oogamy	oogenesis	oogonium
oolites	oolith	ooliths
oolongs	oomiak	oomiaks
oompahs	oophorectomies	oophorectomy
oophoritis	oophyte	oophytes
oos	oosperm	oosperms
oosphere	oospheres	oospore
oospores	ooze	oozes
oozing

159 Nouns Beginning With OP

Ophir	(in the Bible) an unidentified region, perhaps in southeastern Arabia, famous for its fine gold and precious stones.
opah	A large deep-bodied fish with a deep blue back, silvery belly, and crimson fins, living in deep oceanic waters.
opinions	a view, judgment, or appraisal formed in the mind about a particular matter
opossum	An American marsupial which has a naked prehensile tail and hind feet with an opposable thumb.
ops	informal Observation post. (in the theater) opposite prompt. Organophosphate(s). (in the Roman Catholic Church) Ordo Praedicatorum Order of Preachers (Dominican). (in online forums or comment pages) original post (or poster).
optic	Relating to the eye or vision. A lens or other optical component in an optical instrument. archaic, humorous

Ophelia	Ophiuchus	Oporto
Oppenheimer	opacities	opacity
opahs	opal	opalescence
opaline	opalines	opals
opaqueness	opaques	opcode
opcodes	open	open-heartedness
open-mindedness	openers	opening
openings	openness	opens
openwork	opepe	opepes
opera	operability	operagoer
operagoers	operand	operands
operant	operants	operas
operation	operations	operative
operativeness	operatives	operator
operators	operculum	operetta
operettas	operettist	operettists
operon	operons	operoseness
ophicleide	ophicleides	ophidian
ophidians	ophiolater	ophiolaters
ophiolatry	ophiologist	ophiologists
ophiology	ophite	ophites
ophthalmia	ophthalmitis	ophthalmologist
ophthalmology	ophthalmometer	ophthalmometers
ophthalmometry	ophthalmoscope	ophthalmoscopes
ophthalmoscopy	opiate	opiates
opinicus	opinicuses	opinion
opinionativeness	opisthobranch	opisthobranchs
opisthodomos	opisthodomoses	opium
opiumism	opiums	opodeldoc
opopanax	opossums	oppidan

oppidans	oppilation	opponencies
opponency	opponent	opponents
opportuneness	opportunism	opportunist
opportunists	opportunities	opportunity
opposability	opposer	opposers
opposite	oppositeness	opposites
opposition	oppositions	oppression
oppressions	oppressiveness	oppressor
oppressors	opprobriousness	opprobrium
oppugner	oppugners	opsimath
opsimaths	opsonin	optative
optatives	optician	opticians
optics	optime	optimes
optimise	optimises	optimism
optimist	optimists	optimization
optimizations	optimum	option
options	optometer	optometers
optometrist	optometrists	optometry
opulence	opuntia	opuntias
opus	opuscule	opuscules
opuses

339 Nouns That Start With OR

Oran	A port on the Mediterranean coast of Algeria; population 679,900 (est. 2009).
Oregon	A state in the northwestern US, on the coast of the Pacific Ocean; population 3,790,060 (est. 2008); capital, Salem. Britain ceded the territory to the US in 1846 and it became the 33rd state in 1859.
Orestes	The son of Agamemnon and Clytemnestra and the brother of Electra and Iphigenia. He killed his mother and her lover Aegisthus to avenge the murder of Agamemnon.
Origen	(c. 185–c. 254), Christian scholar and theologian, probably born in Alexandria, Egypt. His most well-known work was the Hexapla, an edition of the Old Testament with six or more parallel versions.
Orinoco	A river in northern South America that rises in southeastern Venezuela and flows 1,280 miles (2,060 km), entering the Atlantic Ocean through a vast delta. For part of its length it forms the border between Colombia and Venezuela.
Orion	Greek Mythology Astronomy postpositive
Orlando	A city in central Florida; population 230,519 (est. 2008). It is a popular tourist resort.
Orlon	A synthetic acrylic fiber used for textiles and knitwear, or a fabric made from it.
Orne	Ornate, ornamental. Chiefly as postpositive, especially in cottage orné.
Orpheus	A poet who could entrance wild beasts with the beauty of his singing and lyre playing. He went to the underworld after the death of his wife Eurydice and secured her release from the dead, but lost her because he failed to obey the condition that he must not look back at her until they had reached the world of the living.
Orphism	A mystic religion of ancient Greece, originating in the 7th or 6th century BC and based on poems (now lost) attributed to Orpheus, emphasizing the necessity for individuals to rid themselves of the evil part of their nature by ritual and moral purification throughout a series of reincarnations. A short-lived art movement (c. 1912) within cubism, pioneered by a group of French painters (including Robert Delaunay, Sonia Delaunay-Terk, and Fernand Léger) and emphasizing the lyrical use of color rather than the austere intellectual cubism of Picasso, Braque, and Gris.
Orvieto	A town in Umbria, in central Italy in the middle of a wine-producing area; population 21,059 (2008). A white wine made near Orvieto.
orach	A plant of the goosefoot family with leaves that are sometimes covered in a white mealy substance. Several kinds are edible and can be used as a substitute for spinach or sorrel.
orache	A plant of the goosefoot family with leaves that are sometimes covered in a white mealy substance. Several kinds are edible and can be used as a substitute for spinach or sorrel.
oraches	A plant of the goosefoot family with leaves that are sometimes covered in a white mealy substance. Several kinds are edible and can be used as a substitute for spinach or sorrel.
orachs	A plant of the goosefoot family with leaves that are sometimes covered in a white mealy substance. Several kinds are edible and can be used as a substitute for spinach or sorrel.
oracle	A priest or priestess acting as a medium through whom advice or prophecy was sought from the gods in classical antiquity. archaic
oracles	A priest or priestess acting as a medium through whom advice or prophecy was sought from the gods in classical antiquity. archaic
oracy	The ability to express oneself fluently and grammatically in speech.
oral	By word of mouth; spoken rather than written. Relating to the mouth. often orals
orals	By word of mouth; spoken rather than written. Relating to the mouth. often orals
orange	A town in southern France, on the Rhône River, home of the ancestors of the Dutch royal house. A city in southwestern California, southeast of Los Angeles in an agricultural area; population 136,392 (est. 2008). Relating to the Orange Order. A round juicy citrus fruit with a tough bright reddish-yellow rind. A bright reddish-yellow color like that of the skin of a ripe orange. Reddish yellow.
orarion	#ERROR!
orarium	An ecclesiastical stole; (now) specifically the stole worn by a deacon in the Greek and Russian Orthodox Churches.
oration	A formal speech, especially one given on a ceremonial occasion.
orator	A public speaker, especially one who is eloquent or skilled.
oratory	A small chapel, especially for private worship.The art or practice of formal speaking in public.
oratrix	A female plaintiff or petitioner. Now rare (chiefly US Law).
orb	A spherical body; a globe. literary
orbit	The curved path of a celestial object or spacecraft around a star, planet, or moon, especially a periodic elliptical revolution.A sphere of activity, interest, or application.Anatomy (of a celestial object or spacecraft) move in orbit around (a star or planet)
orbital	Relating to an orbit or orbits.Each of the actual or potential patterns of electron density that may be formed in an atom or molecule by one or more electrons, and that can be represented as a wave function.
orbits	The curved path of a celestial object or spacecraft around a star, planet, or moon, especially a periodic elliptical revolution.A sphere of activity, interest, or application.Anatomy (of a celestial object or spacecraft) move in orbit around (a star or planet)
orbs	A spherical body; a globe. literary
orc	(in fantasy literature and games) a member of an imaginary race of humanlike creatures, characterized as ugly, warlike, and malevolent.
orcein	A red dye obtained from orchil, used as a stain in microscopic study.
orchard	A piece of land planted with fruit trees.
orchid	A plant with complex flowers that are often showy or bizarrely shaped, having a large specialized lip (labellum) and frequently a spur. Orchids occur worldwide, especially as epiphytes in tropical forests, and are valuable hothouse plants.
orchil	A red or violet dye obtained from certain lichens, used as a source of litmus, orcinol, and other pigments.A lichen with flattened fronds from which a red or violet dye can be obtained.
orchis	An orchid of (or formerly of) a genus native to north temperate regions, characterized by a tuberous root and an erect fleshy stem bearing a spike of typically purple or pinkish flowers.
orcinol	A crystalline compound extracted from certain lichens and used to make dyes.
orcs	(in fantasy literature and games) a member of an imaginary race of humanlike creatures, characterized as ugly, warlike, and malevolent.
ord	Order.Ordinary.
ordeal	A painful or horrific experience, especially a protracted one. historical
order	The arrangement or disposition of people or things in relation to each other according to a particular sequence, pattern, or method.An authoritative command, direction, or instruction.A particular social, political, or economic system.in singularBiology Any of the five classical styles of architecture (Doric, Ionic, Corinthian, Tuscan, and Composite) based on the proportions of columns, amount of decoration, etc.Military Mathematics reporting verbwith objectwith object
orders	The arrangement or disposition of people or things in relation to each other according to a particular sequence, pattern, or method.An authoritative command, direction, or instruction.A particular social, political, or economic system.in singularBiology Any of the five classical styles of architecture (Doric, Ionic, Corinthian, Tuscan, and Composite) based on the proportions of columns, amount of decoration, etc.Military Mathematics reporting verbwith objectwith object
ordure	Excrement; dung.
ore	A naturally occurring solid material from which a metal or valuable mineral can be profitably extracted.A monetary unit of Sweden, equal to one hundredth of a krona.
oread	A nymph believed to inhabit mountains.
oreads	A nymph believed to inhabit mountains.
ores	A naturally occurring solid material from which a metal or valuable mineral can be profitably extracted.A monetary unit of Sweden, equal to one hundredth of a krona.
orexis	Appetite; physical desire.
organ	A part of an organism that is typically self-contained and has a specific vital function, such as the heart or liver in humans.A department or organization that performs a specified function.
organa	(in medieval music) a form of early polyphony based on an existing plainsong.
organs	A part of an organism that is typically self-contained and has a specific vital function, such as the heart or liver in humans.A department or organization that performs a specified function.
orgasm	A climax of sexual excitement, characterized by feelings of pleasure centered in the genitals and (in men) experienced as an accompaniment to ejaculation.Experience an orgasm.
orgeat	A cooling drink made from orangeflower water and either barley or almonds.
orgies	A wild party, especially one involving excessive drinking and unrestrained sexual activity.
orgy	A wild party, especially one involving excessive drinking and unrestrained sexual activity.
oribi	A small antelope of the African savanna, having a reddish-beige back, white underparts, and short vertical horns.
oribis	A small antelope of the African savanna, having a reddish-beige back, white underparts, and short vertical horns.
oriel	A projection from the wall of a building, typically supported from the ground or by corbels.
oriels	A projection from the wall of a building, typically supported from the ground or by corbels.
orient	the OrientThe special luster of a pearl of the finest quality. literary with objectAdjust or tailor (something) to specified circumstances or needs.
origan	Any plant of the genus Origanum; especially wild marjoram or oregano, O. vulgare. In early use also
origin	The point or place where something begins, arises, or is derived.Anatomy Mathematics
oriole	An Old World bird related to the starlings that feeds on fruit and insects, the male typically having bright yellow and black plumage.A New World bird of the American blackbird family, with black and orange or yellow plumage.
orison	A prayer.
orle	A narrow border inset from the edge of a shield.
orles	A narrow border inset from the edge of a shield.
orlop	The lowest deck of a wooden sailing ship with three or more decks.
orlops	The lowest deck of a wooden sailing ship with three or more decks.
ormolu	A gold-colored alloy of copper, zinc, and tin used in decorating furniture and making ornaments. The term originally referred to a process in which powdered gold was mixed with mercury and used to gild metal, a technique that was banned in the 19th century on account of its toxicity.
ornis	The birds of a region collectively; = “avifauna”.
oroide	An alloy of copper and zinc having the colour of gold.
orphan	A child whose parents are dead.Printing Make (a person or animal) an orphan.
orpin	Fretting, murmuring.
orpine	A purple-flowered Eurasian plant of the stonecrop family, a naturalized weed of North America.
orpins	A purple-flowered Eurasian plant of the stonecrop family, a naturalized weed of North America.
orrery	A mechanical model of the solar system, or of just the sun, earth, and moon, used to represent their relative positions and motions.
orris	A preparation of the fragrant rootstock of an iris, used in perfumery and formerly in medicine.
oryx	Any of several species of antelopes native to arid regions of Africa and Asia, having dark markings on the face and long, pointed horns.
oryxes	Any of several species of antelopes native to arid regions of Africa and Asia, having dark markings on the face and long, pointed horns.
orzo	A variety of pasta shaped like grains of barley or rice.

Orangeism	Orangeman	Orcadian
Orcadians	Orcus	Orczy
Ordovician	Oreopithecus	Oresteia
Orfeo	Orff	Orientalism
Orientalist	Orientalists	Origenism
Origenist	Origenists	Orissa
Oriya	Orleanism	Orleanist
Orly	Ormandy	Ormazd
Orpington	Orsini	Orsino
Orson	Orton	Orwell
oracularity	oracularness	orang
orang-utan	orang-utans	orange-tip
orangeade	orangeades	orangeries
orangery	orangs	orarions
orariums	orations	oratories
oratorio	oratorios	oratrixes
orbicularis	orbitals	orchardist
orchardists	orchards	orchestra
orchestras	orchestration	orchestrations
orchestrator	orchestrators	orchestrion
orchestrions	orchidectomies	orchidectomy
orchidologist	orchidologists	orchidology
orchids	orchiectomies	orchiectomy
orchils	orchises	orchitis
ordainer	ordainers	ordaining
ordainment	ordainments	ordeals
ordering	orderings	orderlies
orderliness	ordinals	ordinance
ordinances	ordinand	ordinands
ordinaries	ordinariness	ordinary

ordinate	ordinates	ordination
ordinations	ordnance	ordnances
ordonnance	ords	ordures
oreades	oregano	oreganos
orexises	orfe	orfes
organ-grinder	organ-grinders	organdie
organdy	organelle	organelles
organic	organicism	organicist
organicists	organisability	organisation
organisations	organism	organisms
organist	organists	organizability
organization	organizations	organizer
organizers	organogenesis	organography
organon	organotherapy	organum
organza	organzas	organzine
orgasms	orgeats	oriental
orientals	orientation	orientations
orienteering	orients	orifice
orifices	oriflamme	oriflammes
origami	origanes	origans
origanum	origanums	original
originality	originals	origination
originator	originators	origins
orinasal	orinasals	orioles
orisons	orleans	ormer
ormers	ormolus	ornament
ornamental	ornamentation	ornamentations
ornaments	ornateness	orneriness
ornises	ornithischian	ornithischians
ornithogalum	ornithogalums	ornithologist

ornithologists	ornithology	ornithomancy
ornithopod	ornithopods	ornithopter
ornithopters	ornithorhynchus	ornithoscopy
ornithosis	orogenies	orogeny
orographic	orography	orologist
orologists	oropharynx	orotundity
orphanage	orphanages	orphanhood
orphans	orpharion	orpharions
orphrey	orphreys	orpiment
orpines	orreries	orrises
orseille	orseilles	ortanique
ortaniques	orthicon	orthicons
orthocentre	orthocentres	orthoclase
orthodontia	orthodontics	orthodontist
orthodontists	orthodoxies	orthodoxy
orthoepy	orthogenesis	orthographer
orthographers	orthographies	orthography
orthopaedics	orthopedics	orthopedist
orthopedists	orthophosphate	orthophosphates
orthopraxies	orthopraxy	orthopsychiatry
orthoptera	orthopteran	orthopteron
orthoptics	orthostichies	orthostichy
orthotone	orthotropism	orthros
orthroses	ortolan	ortolans

121 Nouns Starting With OS

Osage	A member of a North American people formerly inhabiting the Osage River valley in Missouri. The Siouan language of the Osage. Relating to the Osage or their language.
Osages	A member of a North American people formerly inhabiting the Osage River valley in Missouri. The Siouan language of the Osage. Relating to the Osage or their language.
Osaka	A port and commercial city in central Japan, on the island of Honshu; population 2,510,459 (2007).
Oscan	An extinct Italic language of southern Italy, related to Umbrian and surviving in inscriptions mainly of the 4th to 1st centuries BC. Relating to Oscan.
Oscar	trademark in US A code word representing the letter O, used in radio communication. Money. A South American cichlid fish with velvety brown young and multicolored adults, popular in aquariums.
Osiris	A god originally connected with fertility, husband of Isis and father of Horus. He is known chiefly through the story of his death at the hands of his brother Seth and his subsequent restoration to a new life as ruler of the afterlife.
Oslo	The capital and chief port of Norway, on the southern coast at the head of Oslofjord; population 839,423 (2007). Founded in the 11th century, it was known as Christiania (or Kristiania) from 1624 until 1924 in honor of Christian IV of Norway and Denmark (1577–1648).
Osmanli	Relating to the Ottoman empire or to the Turkish dynasty of Osman I (Othman I). A Turk, especially of the period of the Ottoman empire.
Osmanlis	Relating to the Ottoman empire or to the Turkish dynasty of Osman I (Othman I). A Turk, especially of the period of the Ottoman empire.
Ossian	A legendary Irish warrior and bard, whose name became well known in 1760–63 when the Scottish poet James Macpherson (1736–96) published his own verse as an alleged translation of 3rd-century Gaelic tales.
Ossies	(in Germany) a citizen of the former German Democratic Republic.
Ostend	A port on the North Sea coast of northwestern Belgium, in West Flanders; population 69,175 (2008). It is a major ferry port with links to Dover. French name Ostende.
Ostrogoth	A member of the eastern branch of the Goths, who conquered Italy in the 5th–6th centuries AD.
Ostyak	A member of a people of the Ob River basin in Western Siberia. Now usually called Khanty. The Ob-Ugrian language of this people; = “Khanty”. Of, relating to, or designating the Ostyaks or their language.
oscillation	Movement back and forth at a regular speed. Physics
oscillations	Movement back and forth at a regular speed. Physics
oscillator	A device for generating oscillatory electric currents or voltages by nonmechanical means.
oscillators	A device for generating oscillatory electric currents or voltages by nonmechanical means.
oscillogram	A record produced by an oscillograph.
oscillograms	A record produced by an oscillograph.
oscillograph	A device for recording oscillations, especially those of an electric current.
oscilloscope	A device for viewing oscillations, as of electrical voltage or current, by a display on the screen of a cathode ray tube.
oscine	Relating to or denoting passerine birds of a large division that includes the songbirds. A bird of the oscine division.
oscitancy	Drowsiness as evidenced by yawning; dullness; indolence, negligence, inattention.
osculum	A large aperture in a sponge through which water is expelled.
osier	A small Eurasian willow that grows mostly in wet habitats and is a major source of the long flexible shoots (withies) used in basketwork. US
osiers	A small Eurasian willow that grows mostly in wet habitats and is a major source of the long flexible shoots (withies) used in basketwork. US
osmeterium	An organ capable of emitting a penetrating or noxious odour; specifically an eversible gland on the first thoracic segment of certain papilionid caterpillars.
osmiridium	A naturally occurring alloy of osmium and iridium, often with traces of other metals; (Mineralogy) an alloy having a cubic crystal structure and in which iridium predominates.
osmium	The chemical element of atomic number 76, a hard, dense silvery-white metal of the transition series.
osmometer	An instrument for demonstrating or measuring osmotic pressure.
osmometers	An instrument for demonstrating or measuring osmotic pressure.
osmose	Pass by or as if by osmosis.
osmoses	Pass by or as if by osmosis.
osmosis	Biology Chemistry The process of gradual or unconscious assimilation of ideas, knowledge, etc.
osmund	A plant of a genus that includes the royal and cinnamon ferns.
osmunda	A plant of a genus that includes the royal and cinnamon ferns.
osmundas	A plant of a genus that includes the royal and cinnamon ferns.
osmunds	A plant of a genus that includes the royal and cinnamon ferns.
osnaburg	A kind of coarse, heavy linen or cotton used for such items as furnishings and sacks.
osnaburgs	A kind of coarse, heavy linen or cotton used for such items as furnishings and sacks.
osprey	A large fish-eating bird of prey with long, narrow wings and a white underside and crown, found throughout the world.
ospreys	A large fish-eating bird of prey with long, narrow wings and a white underside and crown, found throughout the world.
ossa	A bone (used chiefly in Latin names of individual bones, e. g. os trapezium). An opening or entrance to a passage, especially one at either end of the cervix of the uterus. The chemical element osmium. (in calculating dates) Old Style. Computing Ordinary Seaman. (in the UK) Ordnance Survey. (as a size of clothing) outsize. Out of stock. Overseas.
ossein	The collagen of bones, used for glues and gelatin, derived by dissolving the mineral content in an acid solution.
osselet	Zoology Anatomy rare Medicine
osselets	Zoology Anatomy rare Medicine
ossicle	Anatomy Zoology
ossicles	Anatomy Zoology
ossifrage	A bird of prey reputed to break bones by dropping them from a great height (usually identified with the lammergeier or bearded vulture, Gypaetus barbatus).
ossifrages	A bird of prey reputed to break bones by dropping them from a great height (usually identified with the lammergeier or bearded vulture, Gypaetus barbatus).
ossuaries	A container or room in which the bones of dead people are placed.
ossuary	A container or room in which the bones of dead people are placed.
osteitis	Inflammation of the substance of a bone.
ostentation	Pretentious and vulgar display, especially of wealth and luxury, intended to impress or attract notice.
osteoblast	A cell that secretes the matrix for bone formation.
osteoblasts	A cell that secretes the matrix for bone formation.
osteoclasis	Surgery Pathology Physiology
osteoclast	A large multinucleate bone cell which absorbs bone tissue during growth and healing.
osteoclasts	A large multinucleate bone cell which absorbs bone tissue during growth and healing.
osteogenesis	The formation of bone.
osteology	The study of the structure and function of the skeleton and bony structures.
osteoma	A tumour of bone; specifically a well-circumscribed benign tumour composed of compact or trabecular bone, usually occurring in a bone of the skull.
osteomalacia	Softening of the bones, typically through a deficiency of vitamin D or calcium.
osteomas	A tumour of bone; specifically a well-circumscribed benign tumour composed of compact or trabecular bone, usually occurring in a bone of the skull.
osteopath	A practitioner of osteopathy.
osteopathist	A practitioner of osteopathy; an osteopath.
osteopaths	A practitioner of osteopathy.
osteopathy	A branch of medical practice that emphasizes the treatment of medical disorders through the manipulation and massage of the bones, joints, and muscles.
osteophyte	A bony outgrowth associated with the degeneration of cartilage at joints.
osteophytes	A bony outgrowth associated with the degeneration of cartilage at joints.
osteoplasty	Reparative or reconstructive surgery of the bones; bone grafting; an instance of this.
osteoporosis	A medical condition in which the bones become brittle and fragile from loss of tissue, typically as a result of hormonal changes, or deficiency of calcium or vitamin D.
osteosarcoma	A malignant tumor of bone in which there is a proliferation of osteoblasts.
osteotome	A surgical instrument for cutting bone, typically resembling a chisel.
osteotomes	A surgical instrument for cutting bone, typically resembling a chisel.
osteotomies	The surgical cutting of a bone or removal of a piece of bone.
osteotomy	The surgical cutting of a bone or removal of a piece of bone.
ostiaries	A doorkeeper, especially of a church; specifically a member of the lowest of the four lesser orders in the pre-Reformation Western Church, and later in the Roman Catholic Church.
ostiary	A doorkeeper, especially of a church; specifically a member of the lowest of the four lesser orders in the pre-Reformation Western Church, and later in the Roman Catholic Church.
ostinato	A continually repeated musical phrase or rhythm.
ostinatos	A continually repeated musical phrase or rhythm.
ostiole	(in some small algae and fungi) a small pore through which spores are discharged.
ostioles	(in some small algae and fungi) a small pore through which spores are discharged.
ostium	Anatomy Zoology
ostler	A man employed to look after the horses of people staying at an inn.
ostracise	Exclude (someone) from a society or group.
ostracises	Exclude (someone) from a society or group.
ostracism	Exclusion from a society or group. (in ancient Greece) temporary banishment from a city by popular vote.
ostracod	A minute aquatic crustacean of the class Ostracoda.
ostracoderm	An extinct jawless fish of the Cambrian to Devonian periods, having a heavily armored body.
ostracods	A minute aquatic crustacean of the class Ostracoda.
ostracon	A potsherd used as a writing surface.
ostrich	A flightless swift-running African bird with a long neck, long legs, and two toes on each foot. It is the largest living bird, with males reaching an average height of 8 feet (2. 5 m). A person who refuses to face reality or accept facts.
ostriches	A flightless swift-running African bird with a long neck, long legs, and two toes on each foot. It is the largest living bird, with males reaching an average height of 8 feet (2. 5 m). A person who refuses to face reality or accept facts.

Osbert	Osborne	Oscars
Osric	Ossie	Oswald
oscillographs	oscilloscopes	osculation
osculations	osculums	osmidrosis
osmometry	ossification	ostensories
ostensory	ostentatiousness	osteoarthritis
osteologist	osteologists	osteomyelitis
osteopathists	osteopetrosis	osteoplasties
ostlers

39 Words That Start With OT Nouns

Othello	A trademark for
Otis	Inflammation of the ear, usually distinguished as otitis externa (of the passage of the outer ear), otitis media (of the middle ear), and otitis interna (of the inner ear; labyrinthitis).
Otranto	commune and port on the Strait of Otranto at the southeastern tip of Puglia in southern Italy population5600
Ottawa	The federal capital of Canada, in southeastern Ontario, on the Ottawa River (a tributary of the St. Lawrence River); population 812,129 (2006). From its founding in 1827 until 1854, it was named Bytown after Colonel John By (1779–1836).
Ottoman	A low upholstered seat, or footstool, without a back or arms that typically serves also as a box, with the seat hinged to form a lid. A heavy ribbed fabric made from silk and either cotton or wool, typically used for coats. historical historical A Turk, especially of the period of the Ottoman Empire.
Ottomans	A low upholstered seat, or footstool, without a back or arms that typically serves also as a box, with the seat hinged to form a lid. A heavy ribbed fabric made from silk and either cotton or wool, typically used for coats. historical historical A Turk, especially of the period of the Ottoman Empire.
Otway	Thomas 1652–1685 English dramatist
otalgia	Earache.
otherness	The quality or fact of being different.
otherworldliness	of, relating to, or resembling that of a world other than the actual world
otitis	Inflammation of the ear, usually distinguished as otitis externa (of the passage of the outer ear), otitis media (of the middle ear), and otitis interna (of the inner ear; labyrinthitis).
otocyst	a fluid-containing organ of many invertebrates that contains an otolith
otocysts	a fluid-containing organ of many invertebrates that contains an otolith
otolaryngologist	a physician specializing in otolaryngology
otolaryngologists	a physician specializing in otolaryngology
otolaryngology	The study of diseases of the ear and throat.
otolith	Each of three small oval calcareous bodies in the inner ear of vertebrates, involved in sensing gravity and movement.
otoliths	Each of three small oval calcareous bodies in the inner ear of vertebrates, involved in sensing gravity and movement.
otologist	a science that deals with the ear and its diseases
otologists	a science that deals with the ear and its diseases
otology	The study of the anatomy and diseases of the ear.
otorhinolaryngologist	a physician specializing in otorhinolaryngology
otorhinolaryngologists	a physician specializing in otorhinolaryngology
otorhinolaryngology	a medical specialty concerned especially with the ear, nose, and throat and related parts of the head and neck
otosclerosis	A disorder, sometimes hereditary, in which there is formation of new bone around the base of the stapes (bone of the middle ear), resulting in progressive hearing loss.
otoscope	An instrument designed for visual examination of the eardrum and the passage of the outer ear, typically having a light and a set of lenses.
otoscopes	An instrument designed for visual examination of the eardrum and the passage of the outer ear, typically having a light and a set of lenses.
ottava	at an octave higher or lower than written
otter	A semiaquatic fish-eating mammal of the weasel family, with an elongated body, dense fur, and webbed feet.
otters	A semiaquatic fish-eating mammal of the weasel family, with an elongated body, dense fur, and webbed feet.
otto	a fragrant essential oil (as from rose petals)
ottos	A fragrant essential oil, typically made from rose petals.
ottrelite	A hydroxide and aluminosilicate of magnesium, ferrous iron, and manganese which occurs as greyish to black crystalline scales.

Otello	Otterburn	Ottilie
ottar	ottars	ottavas

184 Nouns Beginning With OU

Oudh	A region of northern India. Joined with Agra in 1877, it formed the United Provinces of Agra and Oudh in 1902 and was renamed Uttar Pradesh in 1950.
Ouse	A river in northeastern England that forms at the confluence of the Ure and Swale Rivers and flows southeast for 57 miles (92 km) through York to the Humber Estuary. A river in southeastern England that flows southeast for 30 miles (48 km) to the English Channel.
ouabain	A toxic compound obtained from certain trees, used as a very rapid cardiac stimulant. It is a polycyclic glycoside.
ouch	Used to express pain.
ouches	A clasp, buckle, fibula, or brooch, especially one set with precious stones, for holding together the two sides of a garment; (hence) a clasped necklace, bracelet, or the like. Also, in later use
ought	Used to indicate duty or correctness, typically when criticizing someone’s actions. Used to indicate something that is probable.
ounce	A very small amount of something.
ounces	A very small amount of something.
ousel	A bird that resembles the blackbird, especially the ring ouzel.
ousels	A bird that resembles the blackbird, especially the ring ouzel.
ouster	North American Law
ousters	North American Law
ousting	Drive out or expel (someone) from a position or place.
out	Moving or appearing to move away from a particular place, especially one that is enclosed or hidden. Situated far or at a particular distance from somewhere. Away from home. So as to be revealed or known. At or to an end. (of a light or fire) so as to be extinguished or no longer burning. (of a jury) considering its verdict in secrecy. Indicating a specified distance away from the goal line or finishing line. (of a party, politician, etc. ) not in office. Through to the outside. Not at home or at one’s place of work. Revealed or made public. No longer alight; extinguished. (of a book, recording, or other product) published or made available. Not concealing one’s sexuality or gender identity. At an end. In a state of unconsciousness. Mistaken; in error. Cricket Baseball informal Baseball the outsReveal the sexual or gender identity of (a person). dated West Indian archaic, literary
outage	A period when a power supply or other service is not available or when equipment is closed down.
outages	A period when a power supply or other service is not available or when equipment is closed down.
outback	The remote and usually uninhabited inland regions of Australia.
outcast	A person who has been rejected by society or a social group. Rejected or cast out.
outcome	The way a thing turns out; a consequence.
outcrop	A rock formation that is visible on the surface. Appear as an outcrop.
outcry	An exclamation or shout.
outer	Outside; external.
outers	Outside; external.
outfall	The place where a river, drain, or sewer empties into the sea, a river, or a lake.
outfit	A set of clothes worn together, typically for a particular occasion or purpose. Provide (someone) with a set of clothes.
outfits	A set of clothes worn together, typically for a particular occasion or purpose. Provide (someone) with a set of clothes.
outflow	A large amount of money, liquid, or people that moves or is transferred out of a place.
outgo	The outlay of money. Go faster than.
outgoer	A person who or animal that goes out; specifically a person who goes out of a place, office, occupation, or tenancy; (Cricket) a dismissed batsman (now rare).
outhaul	A rope used to haul out the clew of a boom sail or the tack of a jib.
outing	A trip taken for pleasure, especially one lasting a day or less. The act or practice of revealing the homosexuality of a person.
outland	Remote or distant territory. Remote; distant.
outlaw	A person who has broken the law, especially one who remains at large or is a fugitive. Ban or make illegal.
outlay	An amount of money spent on something. Expend (an amount of money) on something.
outlet	A pipe or hole through which water or gas may escape. A place from which goods are sold or distributed. A means of expressing one’s talents, energy, or emotions.
outlier	A person or thing situated away or detached from the main body or system.
outline	A line or set of lines enclosing or indicating the shape of an object in a sketch or diagram. A general description or plan giving the essential features of something but not the detail. Draw, trace, or define the outer edge or shape of (something)Give a summary of (something)
outlook	A person’s point of view or general attitude to life. A view.
outness	The quality, fact, or condition of being out; the quality or fact of being external, especially as apprehended by the mind or senses; externality; an example or instance of this. Utterance, outward expression.
output	The amount of something produced by a person, machine, or industry. Electronics Produce, deliver, or supply (data) using a computer or other device.
outs	Moving or appearing to move away from a particular place, especially one that is enclosed or hidden. Situated far or at a particular distance from somewhere. Away from home. So as to be revealed or known. At or to an end. (of a light or fire) so as to be extinguished or no longer burning. (of a jury) considering its verdict in secrecy. Indicating a specified distance away from the goal line or finishing line. (of a party, politician, etc. ) not in office. Through to the outside. Not at home or at one’s place of work. Revealed or made public. No longer alight; extinguished. (of a book, recording, or other product) published or made available. Not concealing one’s sexuality or gender identity. At an end. In a state of unconsciousness. Mistaken; in error. Cricket Baseball informal Baseball the outsReveal the sexual or gender identity of (a person). dated West Indian archaic, literary
outset	The start or beginning of something.
ouzel	A bird that resembles the blackbird, especially the ring ouzel.
ouzels	A bird that resembles the blackbird, especially the ring ouzel.
ouzo	A Greek anise-flavored liqueur.
ouzos	A Greek anise-flavored liqueur.

Ouagadougou	Oujda	ouabains
ouananiche	ouananiches	oubliette
oubliettes	oughts	ouija
ouijas	ouphe	ourari
ouraris	out-and-outer	out-of-doors
out-of-print	out-tray	out-trays
outboard	outbreak	outbreaks
outbuilding	outbuildings	outburst
outbursts	outcaste	outcastes
outcasts	outcomes	outcries
outcropping	outcrops	outcross
outcrosses	outcrossing	outcrossings
outdoors	outerwear	outfalls
outfield	outfielder	outfielders
outfields	outfighting	outfitter
outfitters	outfitting	outflows
outgoers	outgoing	outgoings
outgrowth	outgrowths	outguard
outguards	outhauls	outhouse
outhouses	outlander	outlanders
outlandishness	outlands	outlawry
outliers	outlines	outlooks
outparish	outparishes	outports
outposts	outpouring	outpourings
outpours	outputs	outquarters
outrage	outrageousness	outrages
outrance	outrances	outreach
outreaches	outremer	outremers
outride	outrider	outriders
outrides	outrigger	outriggers

outrunner	outrunners	outrush
outrushes	outsets	outshoot
outshoots	outshot	outshots
outside	outsider	outsiders
outsides	outsize	outsizes
outskirts	outsole	outsoles
outspan	outspans	outspokenness
outspread	outspreads	outstation
outstations	outswing	outswinger
outswingers	outswings	outtake
outturn	outturns	outward
outwardness	outwards	outwash
outwork	outworker	outworkers
outworks

267 Nouns That Start With OV

Ovambo	A member of a people of northern Namibia. The Bantu language of the Ovambo. Relating to the Ovambo or their language.
Ovambos	A member of a people of northern Namibia. The Bantu language of the Ovambo. Relating to the Ovambo or their language.
Ovid	(43 BC–c. AD 17), Roman poet; full name Publius Ovidius Naso. He is noted for his elegiac love poems (such as the Amores and the Ars Amatoria) and for the Metamorphoses, a hexametric series of tales of mythological, legendary, and historical figures.
Oviedo	A city in northwestern Spain, capital of the Asturias region; population 220,644 (2008).
ova	A mature female reproductive cell, especially of a human or other animal, which can divide to give rise to an embryo usually only after fertilization by a male cell.
oval	Having a rounded and slightly elongated outline or shape like that of an egg. A body, object, or design with an oval shape or outline.
ovalbumin	Albumin derived from the white of eggs.
ovals	Having a rounded and slightly elongated outline or shape like that of an egg. A body, object, or design with an oval shape or outline.
ovaries	A female reproductive organ in which ova or eggs are produced, present in humans and other vertebrates as a pair.
ovary	A female reproductive organ in which ova or eggs are produced, present in humans and other vertebrates as a pair.
ovation	A sustained and enthusiastic show of appreciation from an audience, especially by means of applause. Roman History
ovations	A sustained and enthusiastic show of appreciation from an audience, especially by means of applause. Roman History
oven	An enclosed compartment, as in a kitchen range, for cooking and heating food.
ovens	An enclosed compartment, as in a kitchen range, for cooking and heating food.
ovenware	Dishes that can be used for cooking food in the oven.
over	Extending directly upward from. At a higher level or layer than. Higher than or more than (a specified number or quantity)Expressing passage or trajectory across. Expressing duration. By means of; by the medium of. On the subject of. No longer affected by. Expressing passage or trajectory across an area. Beyond and falling or hanging from a point. Used to express action and result. Used to express repetition of a process. (in two-way radio communication) used to indicate that the speaker has finished speaking and is awaiting a reply. Finished or complete. A sequence of six balls bowled by a bowler from one end of the pitch.
overall	Taking everything into account. In all parts; taken as a whole. North American
overalls	Taking everything into account. In all parts; taken as a whole. North American
overbid	(in an auction) make a higher bid than a previous bid. (in competitive bidding, the auction in bridge, etc. ) bid more than is warranted or manageable. A bid that is higher than is justified.
overbids	(in an auction) make a higher bid than a previous bid. (in competitive bidding, the auction in bridge, etc. ) bid more than is warranted or manageable. A bid that is higher than is justified.
overbite	The overlapping of the lower teeth by the upper.
overbuy	Buy more of (something) than one needs.
overbuys	Buy more of (something) than one needs.
overcall	Make a higher bid than an opponent’s bid. An act or instance of making an overcall.
overcast	(of the sky or weather) marked by a covering of gray clouds; dull. (in sewing) edged with stitching to prevent fraying. Clouds covering a large part of the sky. Cover with clouds or shade. Stitch over (an unfinished edge) to prevent fraying.
overcheck	A check pattern superimposed on a color or design. A strap passing over a horse’s head between the ears, to pull up on the bit and make breathing easier.
overcoat	A long warm coat worn over other clothing. A top, final layer of paint or a similar covering.
overdose	An excessive and dangerous dose of a drug. Take an overdose of a drug.
overdrives	an automotive transmission gear that transmits to the drive shaft a speed greater than engine speed
overfall	A turbulent stretch of open water caused by the wind blowing against a current, by a strong current or tide over an underwater ridge, or by a meeting of currents.
overflow	(especially of a liquid) flow over the brim of a receptacle. in singularComputing
overfold	A part of something which is folded over another part.
overhang	Hang or extend outward over. A part of something that sticks out or hangs over another thing.
overhaul	Take apart (a piece of machinery or equipment) in order to examine it and repair it if necessary. British A thorough examination of machinery or a system, with repairs or changes made if necessary.
overhead	Above the level of the head; in the sky. Situated above the level of the head. (of a driving mechanism) above the object driven. attributiveAn overhead cost or expense. A transparency designed for use with an overhead projector. An overhead compartment.
overheat	Make or become too hot. no object
overkill	Excessive use, treatment, or action; too much of something. The amount by which destruction or the capacity for destruction exceeds what is necessary.
overlap	Extend over so as to cover partly. A part or amount which overlaps.
overlaps	Extend over so as to cover partly. A part or amount which overlaps.
overlay	Cover the surface of (something) with a coating. (of a quality or feeling) become more prominent than (a previous quality or feeling)Something laid as a covering over something else. Computing
overlays	Cover the surface of (something) with a coating. (of a quality or feeling) become more prominent than (a previous quality or feeling)Something laid as a covering over something else. Computing
overload	Load with too great a burden or cargo. An excessive load or amount.
overlook	Fail to notice (something)Have a view of from above. archaic archaic A commanding position or view.
overlord	A ruler, especially a feudal lord.
overman	Provide with more people than necessary. An overseer. Philosophy
overmans	Provide with more people than necessary. An overseer. Philosophy
overmast	To provide (a sailing ship) with too high or too heavy a mast or masts.
overmuch	Too much; excessively. Too great in amount; excessive. An excessive amount.
overpass	A bridge by which a road or railroad passes over another. Pass over; traverse.
overplus	A surplus or excess.
override	Use one’s authority to reject or cancel (a decision, view, etc. )Interrupt the action of (an automatic device), typically in order to take manual control. technical Travel or move over. A device for suspending an automatic function on a machine. An excess or increase on a budget, salary, or cost. mainly US
overripe	Too ripe; past its best.
overrun	Spread over or occupy (a place) in large numbers. Continue beyond or above an expected or allowed time or cost. An instance of something exceeding an expected or allowed time or cost. The movement or extension of something beyond an allotted or particular position or space. The movement of a vehicle at a speed greater than is imparted by the engine.
overruns	Spread over or occupy (a place) in large numbers. Continue beyond or above an expected or allowed time or cost. An instance of something exceeding an expected or allowed time or cost. The movement or extension of something beyond an allotted or particular position or space. The movement of a vehicle at a speed greater than is imparted by the engine.
overs	Extending directly upward from. At a higher level or layer than. Higher than or more than (a specified number or quantity)Expressing passage or trajectory across. Expressing duration. By means of; by the medium of. On the subject of. No longer affected by. Expressing passage or trajectory across an area. Beyond and falling or hanging from a point. Used to express action and result. Used to express repetition of a process. (in two-way radio communication) used to indicate that the speaker has finished speaking and is awaiting a reply. Finished or complete. A sequence of six balls bowled by a bowler from one end of the pitch.
overseas	In or to a foreign country, especially one across the sea. From, to, or relating to a foreign country, especially one across the sea.
overseer	A person who supervises others, especially workers.
overshoe	A shoe worn over a normal shoe, typically either of waterproof material to protect the normal shoe in wet weather or of fabric to protect a floor surface.
oversize	Bigger than the usual size.
oversoul	A divine spirit supposed to pervade the universe and to encompass all human souls. The term is associated particularly with Transcendentalism.
overspin	A rotating motion given to a ball when throwing or hitting it, used to give it extra speed or distance or to make it bounce awkwardly.
overtime	Time in addition to what is normal, as time worked beyond one’s scheduled working hours. In addition to normal working hours.
overtone	A musical tone which is a part of the harmonic series above a fundamental note, and may be heard with it. often overtones
overture	An orchestral piece at the beginning of an opera, suite, play, oratorio, or other extended composition. An introduction to something more substantial. usually overtures
overturn	Tip (something) over so that it is on its side or upside down. Abolish, invalidate, or reverse (a previous system, decision, situation, etc. ) rare
overuse	Use (something) too much. Excessive use.
overview	A general review or summary of a subject. Give a general review or summary of.
overword	A repeated word or phrase, especially the burden or refrain of a song; a word or phrase frequently used by an individual.
overwork	Cause (someone) to work beyond their capacity or strength. Make excessive use of. Excessive work.
ovibos	A genus of mammals of the family Bovidae whose only living representative is the musk ox, Ovibos moschatus; (also ovibos) a mammal of this genus, a musk ox (rare).
oviduct	The tube through which an ovum or egg passes from an ovary.
ovisac	A sac containing an ovum or a number of ova.
ovisacs	A sac containing an ovum or a number of ova.
ovoid	(of a solid or a three-dimensional surface) egg-shaped. An ovoid body or surface.
ovoids	(of a solid or a three-dimensional surface) egg-shaped. An ovoid body or surface.
ovolo	A rounded convex molding, in cross section a quarter of a circle or ellipse.
ovule	A small or immature ovum.
ovules	A small or immature ovum.
ovum	A mature female reproductive cell, especially of a human or other animal, which can divide to give rise to an embryo usually only after fertilization by a male cell.

ovariotomies	ovariotomist	ovariotomists
ovariotomy	ovaritis	ovenwood
overabundance	overabundances	overacting
overactivity	overbalance	overbalances
overbearingness	overburden	overburdens
overcapacity	overcapitalisation	overcapitalization
overcasting	overcharge	overcharges
overchecks	overcoating	overcompensation
overcredulity	overdevelopment	overdoses
overdrafts	overdraught	overdraughts
overdresses	overeating	overemphasis
overemphasises	overenthusiasm	overestimate
overestimates	overestimation	overestimations
overexcitability	overexertion	overexertions
overexposure	overfalls	overfeeding
overflight	overflights	overflowing
overflowings	overflows	overfolds
overfondness	overforwardness	overfreedom
overgarment	overgarments	overglazed
overglazing	overgrowth	overgrowths
overhangs	overhastiness	overhauling
overhauls	overheads	overheating
overheats	overindulgence	overindulgences
overissue	overissues	overkills
overlapping	overloads	overlooker
overlookers	overlooks	overlords
overlordship	overmantel	overmantels
overmasts	overmatch	overmatches
overmatter	overmatters	overmeasure
overmeasures	overmultiplication	overnighter

overnighters	overoptimism	overpasses
overpayment	overpayments	overpluses
overpopulation	overpraise	overpraises
overprint	overprints	overproduction
overrashness	overrating	overreaction
overreactions	overreckoning	overrider
overriders	overrides	overruler
overrulers	overscrupulousness	overseers
overshirt	overshirts	overshoes
overshoot	overshoots	oversight
oversights	oversimplification	oversizes
overskirt	overskirts	overslaugh
overslaughs	oversleeve	oversleeves
oversouls	overspecialization	overspill
overspills	overspins	overstand
overstands	overstatement	overstatements
overstock	overstocking	overstocks
overstrain	overstrains	overstudies
overstudy	oversubscription	oversubtlety
oversupplies	oversupply	overtaking
overthrow	overthrower	overthrowers
overthrows	overthrust	overthrusts
overtimes	overtones	overtrick
overtricks	overtures	overturning
overturns	overvaluation	overvaluations
overviews	overweight	overweights
overwords	overworking	overworks
oviparity	oviposition	ovipositor
ovipositors	ovotestis	ovulation
ovulations

17 Nouns Starting With OW

Owen	Robert 1771–1858 Welsh social reformerWilfred 1893–1918 British poet
Owenism	The theory or system of social reform based on communistic cooperation advocated by Robert Owen.
Owenist	Owenite
Owenite	A supporter or advocate of Robert Owen or his proposed system of social reform. Of or relating to Robert Owen or his supporters, or in accordance with his theories of cooperation. A supporter of David Owen or his policies. Of or relating to David Owen, his policies, or his supporters.
Owens	Jesse 1913–1980 James Cleveland Owens American track-and-field athleteriver in eastern California formerly flowing into and now supplying water to the city of Los Angeles by way of the Los Angeles Aqueduct
owelty	Equality. In later use
owl	A nocturnal bird of prey with large forward-facing eyes surrounded by facial disks, a hooked beak, and typically a loud call.
owlet	A small owl found chiefly in Asia and Africa.
owlets	A small owl found chiefly in Asia and Africa.
owlishness	resembling or suggesting an owl
owls	A nocturnal bird of prey with large forward-facing eyes surrounded by facial disks, a hooked beak, and typically a loud call.
owner	A person who owns something.
owner-driver	A person who owns the vehicle they drive as a part of their job.
owner-occupier	a person who owns the dwelling he or she lives in
owners	A person who owns something.
ownership	The act, state, or right of possessing something.
ownerships	The act, state, or right of possessing something.

55 Words That Start With OX Nouns

Oxbridge	Oxford and Cambridge universities regarded together.
Oxford	A city in central England, on the River Thames; population 146,100 (est. 2009). Oxford University is located here. A town in north central Mississippi, home to the University of Mississippi and associated with novelist William Faulkner; population 17,265 (est. 2008).
Oxfordshire	county of south central England; capital Oxfordarea 1044 square miles (2704 square kilometers), population654000
Oxonian	Relating to Oxford, England, or Oxford University. A native or inhabitant of Oxford, England.
Oxonians	a native or resident of Oxford, England
Oxus	river over 1500 miles (2400 kilometers) long in central and western Asia flowing from the Pamirs into the Aral Sea
oxalate	A salt or ester of oxalic acid.
oxalates	A salt or ester of oxalic acid.
oxalis	A plant of a genus which includes the wood sorrel, typically having three-lobed leaves and white, yellow, or pink flowers.
oxalises	A plant of a genus which includes the wood sorrel, typically having three-lobed leaves and white, yellow, or pink flowers.
oxazine	Any of a class of compounds whose molecules contain a ring of one nitrogen, one oxygen, and four carbon atoms, some of which are used as dyes; specifically a monocyclic compound with this structure and the formula C₄ H₅ NO.
oxazines	Any of a class of compounds whose molecules contain a ring of one nitrogen, one oxygen, and four carbon atoms, some of which are used as dyes; specifically a monocyclic compound with this structure and the formula C₄ H₅ NO.
oxcart	a cart drawn by oxen
oxcarts	a cart drawn by oxen
oxen	A castrated bull used as a draft animal.
oxeye	A yellow-flowered North American plant of the daisy family.
oxeyes	any of several composite plants (as of the genera Chrysanthemum or Heliopsis) having heads with both disk and ray flowers
oxgang	A measure of land formerly in use in parts of northern England and Scotland, equivalent to an eighth of a carucate.
oxgangs	A measure of land formerly in use in parts of northern England and Scotland, equivalent to an eighth of a carucate.
oxhide	Leather made from the hide of an ox.
oxidant	An oxidizing agent.
oxidants	An oxidizing agent.
oxidase	An enzyme which promotes the transfer of a hydrogen atom from a particular substrate to an oxygen molecule, forming water or hydrogen peroxide.
oxidases	An enzyme which promotes the transfer of a hydrogen atom from a particular substrate to an oxygen molecule, forming water or hydrogen peroxide.
oxidation	The process or result of oxidizing or being oxidized.
oxidations	the act or process of oxidizing
oxide	A binary compound of oxygen with another element or group.
oxides	A binary compound of oxygen with another element or group.
oxidizations	oxidation
oxidizer	oxidizing agent
oxidizers	oxidizing agent
oxime	Any organic compound containing the group N(OH) attached to a carbon atom, formed by the reaction of hydroxylamine with an aldehyde or ketone. Compare aldoxime , “ketoxime”.
oximes	Any organic compound containing the group N(OH) attached to a carbon atom, formed by the reaction of hydroxylamine with an aldehyde or ketone. Compare aldoxime , “ketoxime”.
oximeter	An instrument for measuring the proportion of oxygenated hemoglobin in the blood.
oximeters	An instrument for measuring the proportion of oxygenated hemoglobin in the blood.
oxlip	A woodland Eurasian primula with yellow flowers that hang down one side of the stem.
oxlips	A woodland Eurasian primula with yellow flowers that hang down one side of the stem.
oxtail	The tail of a cow.
oxtails	The tail of a cow.
oxter	A person’s armpit.
oxters	A person’s armpit.
oxygen	A colorless, odorless reactive gas, the chemical element of atomic number 8 and the life-supporting component of the air.
oxygenate	Supply, treat, charge, or enrich with oxygen.
oxygenates	Supply, treat, charge, or enrich with oxygen.
oxygenation	to impregnate, combine, or supply (something, such as blood) with oxygen
oxygenator	An apparatus for oxygenating the blood.
oxygenators	An apparatus for oxygenating the blood.
oxyhaemoglobin	hemoglobin loosely combined with oxygen that it releases to the tissues — compare deoxyhemoglobin
oxymoron	A figure of speech in which apparently contradictory terms appear in conjunction (e. g. faith unfaithful kept him falsely true)
oxymorons	A figure of speech in which apparently contradictory terms appear in conjunction (e. g. faith unfaithful kept him falsely true)
oxytocic	hastening childbirth
oxytocin	A hormone released by the pituitary gland that causes increased contraction of the uterus during labor and stimulates the ejection of milk into the ducts of the breasts.

oxidisation

oxidisations

6 Nouns Beginning With OY

oyer	a criminal trial held under a commission of oyer and terminer
oyers	a criminal trial held under a commission of oyer and terminer
oyez	A call given by a court officer, or formerly by public criers, typically repeated two or three times to command silence and attention, as before court is in session.
oyezes	a cry of oyez
oyster	Any of a number of bivalve mollusks with rough irregular shells. Several kinds are eaten (especially raw) as a delicacy and may be farmed for food or pearls. An oyster-shaped morsel of meat on each side of the backbone in poultry. Raise, dredge, or gather oysters.
oysters	Any of a number of bivalve mollusks with rough irregular shells. Several kinds are eaten (especially raw) as a delicacy and may be farmed for food or pearls. An oyster-shaped morsel of meat on each side of the backbone in poultry. Raise, dredge, or gather oysters.

10 Nouns That Start With OZ

Ozalid	A photocopy made by a process in which a diazonium salt and coupler are present in the paper coating, so that the image develops in the presence of ammonia.
ozocerite	A brown or black paraffin wax occurring naturally in some shales and sandstones and formerly used in candles, polishes, and electrical insulation.
ozokerite	A brown or black paraffin wax occurring naturally in some shales and sandstones and formerly used in candles, polishes, and electrical insulation.
ozone	A colorless unstable toxic gas with a pungent odor and powerful oxidizing properties, formed from oxygen by electrical discharges or ultraviolet light. It differs from normal oxygen (O₂) in having three atoms in its molecule (O₃).
ozonizer	to treat, impregnate, or combine with ozone
ozonizers	to treat, impregnate, or combine with ozone
ozonosphere	ozone layer

Ozzie

Ozzies

Ozzy

Conclusion

This is just a small sampling of the many great nouns that start with the letter O. While it may be a difficult letter to find words for in some languages, English has no shortage of options. So the next time you’re stuck for a word, try looking to this list for some inspiration.

Oasis, orbit, ocelot, octopus, odyssey, office, oil, onion, opera, and orange are only a few of the many nouns that start with O. With such a wide variety of options, you’re sure to find the perfect word for any situation.

So don’t be afraid to experiment with different words starting with O. After all, the only way to improve your language skills is to try new things. Who knows, you may just find your new favorite word.

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