Words starting with O — 407 entries

The 407 dictionary words that begin with the letter O, in alphabetical order, each with its first definition. Accents do not affect filing: an accented initial is shelved under its base letter.

• operative8 sensesEffectual or important.
• operator15 sensesA person or organisation that operates a device, system, service, etc.
• Ophelia2 sensesA female given name from Ancient Greek.
• opinion7 sensesA belief, judgment or perspective that a person has formed, either through objective or subjective reasoning, about a topic, issue, person or thing.
• opium2 sensesA yellow-brown, addictive narcotic drug obtained from the dried juice of unripe pods of the opium poppy, Papaver somniferum, and containing alkaloids…
• oppa2 sensesAn affectionate term of address for an older brother or somewhat older man.
• opponent7 sensesOne who opposes another; one who works or takes a position against someone or something; one who attempts to stop the progress of someone or…
• opportunity3 sensesA chance for advancement, progress or profit.
• oppose4 sensesTo attempt to stop the progression of; to resist or antagonize by physical means, or by arguments, etc.; to contend against.
• opposed3 sensesActing in opposition; opposing.
• opposing1 senseThat opposes or oppose; on the opposite side.
• opposite16 sensesLocated directly across from something else, or from each other.
• opposition7 sensesThe action of opposing or of being in conflict.
• oppressed1 senseSubject to oppression.
• oppression3 sensesThe exercise of authority or power in a burdensome, cruel, or unjust manner.
• Oprah3 sensesA female given name from Hebrew, of modern usage, variant of Orpah.
• ops2 sensesoperations
• Ops1 senseThe goddess of earth and fertility. Equivalent to the Greek Rhea, Ops was the sister-wife of Saturn and mother of Jupiter. After Saturn learned of a…
• optical6 sensesOf or relating to sight; visual.
• optimism3 sensesa tendency to expect the best, or at least, a favourable outcome
• optimist2 sensesA person who expects a favourable outcome.
• Optimist1 senseA small centreboard sailing dinghy designed to train and introduce young children into sailing.
• optimistic2 sensesExpecting the best in all possible ways.
• Optimus1 senseA pet name for a device, such as a car, computer, or robot.
• option6 sensesOne of a set of choices that can be made.
• or10 sensesConnects at least two alternative words, phrases, clauses, sentences, etc., each of which could make a passage true.
• Or1 senseA surname.
• OR4 sensesInclusive or; either one proposition or the other is true or both.
• oracle12 sensesA shrine dedicated to some prophetic deity.
• Oracle1 senseA database management system (and its associated software) developed by the Oracle Corporation
• oral11 sensesRelating to the mouth.
• Oral2 sensesA male given name from Latin of American usage
• orange13 sensesAn evergreen tree of the genus Citrus such as Citrus sinensis which yields oranges (the fruit).
• Orange26 sensesA city in Vaucluse department, Provence-Alpes-Côte d'Azur, France.
• orb16 sensesA spherical body; a sphere, especially one of the celestial spheres; a sun, planet, or star
• orbit18 sensesThe curved path of one object around a point or another body. An elliptical movement of an object about a celestial object or Lagrange point,…
• orbital4 sensesOf or relating to, or forming an orbit (such as the orbit of a moon, planet, or spacecraft).
• orbiting1 senseThe act or practice of ceasing communication with another person, but continuing to follow them or interact with them on social media.
• orchard2 sensesA garden or an area of land for the cultivation of fruit or nut trees.
• Orchard1 senseA topographic surname.
• orchestra4 sensesA large group of musicians who play together on various instruments, usually including some from strings, woodwind, brass and/or percussion; the…
• orchestral2 sensesRelating to an orchestra or to music played by an orchestra.
• orchid3 sensesA plant of the orchid family (Orchidaceae), bearing unusually-shaped flowers of beautiful colours.
• ordeal3 sensesA painful or trying experience.
• order31 sensesArrangement, disposition, or sequence.
• Order1 senseThe Order of the Arrow.
• ordered2 sensesIn order, not messy, tidy.
• ordering3 sensesArrangement in a sequence.
• orderly8 sensesNeat and tidy; possessing order.
• Orders1 senseA surname
• ordinance6 sensesA local law, passed by e.g. a city.
• ordinarily3 sensesUsually or as a general rule; commonly.
• ordinary18 sensesA person with authority; authority, ordinance. A person having immediate jurisdiction in a given case of ecclesiastical law, such as the bishop…
• Ordinary1 senseThe part of the Roman Catholic Mass that is the same every day
• ore4 sensesRock or other material that contains valuable or utilitarian materials; primarily a rock containing metals or gems for which it is typically mined…
• Ore3 sensesA suburban area, formerly a village, in Hastings borough, East Sussex, England (OS grid ref TQ8311).
• Oregon13 sensesA state in the Pacific Northwest region of the United States. Capital: Salem. Largest city: Portland.
• organ9 sensesThe larger part of an organism, composed of tissues that perform similar functions.
• Organ2 sensesA surname.
• organic13 sensesPertaining to or derived from living organisms.
• organisation1 senseNon-Oxford British English and Australian standard spelling of organization.
• organise1 senseNon-Oxford British standard spelling of organize.
• organism3 sensesA discrete and complete living thing, such as animal, plant, fungus or microorganism.
• organization5 sensesThe quality of being organized.
• organize5 sensesTo arrange in working order.
• organized4 sensesOf things or settings, having been organized; in good order.
• organizing1 senseThe act or process by which something is organized.
• orgasm4 sensesA rush of sexual excitement; now specifically, the climax or peak of sexual pleasure, which occurs during sexual activity and which in males may…
• orgy3 sensesA secret rite or ceremony, typically involving riotous and dissolute behavior, including dancing, drunkenness and indiscriminate sexual activity,…
• Ori2 sensesAn individual's spiritual intuition and destiny, according to Yoruba beliefs.
• orient15 sensesUsually preceded by the: alternative letter-case form of Orient (“a region or a part of the world to the east of a certain place; countries of Asia,…
• Orient14 sensesUsually preceded by the: a region or a part of the world to the east of a certain place; countries of Asia, the East (especially East Asia).
• Oriental9 sensesOf a pearl or other precious stone: having a superior lustre.
• orientation11 sensesThe determination of the relative position of something or someone.
• origin6 sensesThe beginning of something.
• Origin1 sensethe State of Origin series (an annual best-of-three rugby league series between New South Wales and Queensland, nicknamed the "Blues" and the…
• original12 sensesRelating to the origin or beginning; preceding all others.
• originally2 sensesAs it was in the beginning; at first.
• Orion13 sensesA giant-hunter, pursuer of the Pleiades and lover of Eos, and killed by Artemis.
• Orlando3 sensesA male given name from Italian.
• Orleans15 sensesA city, the capital of Loiret department, France; the regional capital of Centre-Val de Loire.
• ornament7 sensesAn element of decoration; that which embellishes or adorns.
• Ornaments1 senseThe forty-third sura (chapter) of the Qur'an.
• orphan10 sensesA person, especially a minor, both or (rarely) one of whose parents have died.
• orphanage2 sensesA residential institution for the care and protection of orphans.
• Orson2 sensesA surname.
• orthodox5 sensesConforming to the accepted, established, or traditional doctrines of a given faith, religion, or ideology.
• Orthodox6 sensesOf or pertaining to the Orthodox Churches collectively.
• Ortiz1 senseA surname from Spanish.
• os3 sensesSynonym of bone.
• OS1 senseAn Ordnance Survey map.
• Osaka3 sensesA placename The capital city of Osaka Prefecture, Japan.
• Osama1 senseA male given name from Arabic.
• Osborne10 sensesAn English surname transferred from the given name.
• oscar1 senseA cichlid fish of species Astronotus ocellatus, native to South America, sometimes kept in aquariums.
• Oscar11 sensesA male given name from Irish or Old English.
• Osgood8 sensesA surname.
• Oslo5 sensesA county and municipality, the capital city of Norway. Formerly called Christiania and Kristiania.
• ostrich5 sensesA large flightless bird of the order Struthioniformes.
• Oswald6 sensesA surname originating as a patronymic.
• ot1 senseThe name of the Cyrillic script letter Ѿ / ѿ.
• other11 sensesSee other (determiner) below.
• Other3 sensesRadical alterity or otherness conceived or reified as a separate entity; “other people” altogether in their difference from oneself.
• others2 sensesOther people.
• otherwise4 sensesDifferently, in another way.
• Otis3 sensesA surname transferred from the given name, notably of the American revolutionary hero James Otis and the innovator and industrialist Elisha Otis.
• otter4 sensesAn aquatic or marine carnivorous mammal in the subfamily Lutrinae.
• Otter1 senseA river with its source in the Blackdown Hills, Somerset, and which flows through Devon, to Lyme Bay in the English Channel.
• Otto12 sensesA male given name from the Germanic languages.
• ottoman3 sensesAn upholstered sofa, without arms or a back, sometimes with a compartment for storing linen etc.
• Ottoman9 sensesArchaic form of Osman, the name borne by Osman I (d. 1323/4), founder of the Ottoman Empire.
• ou2 sensesA probably extinct species of Hawaiian honeycreeper, Psittirostra psittacea.
• ouch7 sensesAn expression of one's own physical pain.
• Ouch1 senseA surname.
• ought5 sensesIndicating duty or obligation.
• oui1 senseSynonym of yes.
• ounce8 sensesAn avoirdupois ounce, weighing ¹⁄₁₆ of an avoirdupois pound, or 28.349523125 grams.
• our9 sensesBelonging to us, excluding the person(s) being addressed (exclusive our).
• ours8 sensesThat or those belonging to us. Excluding the person(s) being addressed (exclusive ours)
• ourselves4 sensesUs; the group including the speaker as the object of a verb or preposition when that group also is the subject.
• out58 sensesAway from the inside or centre.
• out-6 sensesExternal to, on the outside of
• outbreak5 sensesAn eruption; the sudden appearance of a rash, disease, etc.
• outburst3 sensesAn intense period of activity.
• outcast6 sensesTo cast out; to banish.
• outcome4 sensesThat which is produced or occurs as a result of an event or process.
• outdated2 sensesOut of date, old-fashioned, antiquated.
• outdoor3 sensesSituated in, designed to be used in, or carried on in the open air.
• outdoors3 sensesNot inside a house or under covered structure; unprotected; in the open air.
• outer12 sensesOutside; external.
• outfit8 sensesA set of clothing (with accessories).
• outgoing6 sensesExtroverted: talkative, friendly, and social, especially with respect to meeting new people easily and comfortably; outgiving.
• outing4 sensesA pleasure trip or excursion.
• outlaw12 sensesA fugitive from the law.
• Outlaw1 senseA surname transferred from the nickname.
• outlet5 sensesA vent or similar passage to allow the escape of something.
• outline11 sensesA line marking the boundary of an object figure.
• outlook10 sensesA place from which something can be viewed.
• outpost5 sensesA military post stationed at a distance from the main body of troops.
• output7 sensesThat which is produced by something, especially that which is produced within a particular time period or from a particular effort. Production;…
• outrage8 sensesAn excessively violent or vicious attack; an atrocity.
• outrageous4 sensesViolating morality or decency; provoking indignation or affront.
• outright9 sensesWholly; completely; entirely.
• outrun5 sensesTo run faster than.
• outside27 sensesThe part of something that faces out; the outer surface.
• Outside1 senseThe United States excluding Alaska, (especially) the contiguous 48 states south of Canada.
• outsider4 sensesOne who is not part of a community or organization.
• outsiders1 senseA pair of nippers for turning a key in a keyhole from the outside.
• outskirts1 senseThe area surrounding a city or town; suburb.
• outstanding5 sensesProminent or noticeable; sovereign.
• outta1 senseOut of.
• outward9 sensesOuter; located towards the outside.
• oval7 sensesAn elongated round shape resembling an ellipse or an egg. A two-dimensional one.
• Oval1 senseA cricket ground in South London.
• oven3 sensesA chamber used for baking or heating.
• over60 sensesFinished; ended; concluded.
• Over5 sensesA village and civil parish in South Cambridgeshire district, Cambridgeshire, England (OS grid ref TL3770).
• overall5 sensesAll-encompassing, all around.
• overboard5 sensesOutside of a boat; in the water.
• overcome9 sensesTo surmount (a physical or abstract obstacle); to prevail over, to get the better of.
• overdo4 sensesTo do too much; to exceed what is proper or true in doing; to carry too far.
• overdose4 sensesAn excessive and dangerous dose of a drug.
• overdue3 sensesLate; especially, past a deadline or too late to fulfill a need.
• overflowing1 senseoverflow
• overhead18 sensesLocated above, especially over the head.
• overhear1 senseTo hear something that was not meant for one's ears.
• overlapping2 sensesThat overlaps something else
• overload8 sensesTo load excessively.
• overlook9 sensesA vista or point that gives a view down toward something else.
• overlooked1 senseMissed, unnoticed.
• overly8 sensesTo an excessive degree.
• overnight11 sensesDuring or throughout the night, especially during the evening or night just past.
• overrated1 senseGiven an undue amount of credit for quality or merit in a field; not necessarily related to popularity.
• override10 sensesTo ride across or beyond something.
• overrun13 sensesTo defeat an enemy and invade in great numbers, seizing the enemy positions conclusively.
• overseas5 sensesAbroad, especially across the sea.
• oversee5 sensesTo survey, look at something in a wide angle.
• oversight5 sensesAn omission; something that is left out, missed, or forgotten.
• overtake4 sensesTo pass a slower moving object or entity (on the side closest to oncoming traffic).
• overthrow7 sensesTo bring about the downfall of (a government, etc.), especially by force; to usurp.
• overtime7 sensesWorking time outside of one's regular hours.
• overweight9 sensesHaving a higher weight, especially body fat, than what is generally considered healthy for a given body type and height.
• overwhelmed2 sensesEmotionally overpowered.
• overwhelming4 sensesOverpowering, staggering, or irresistibly strong.
• ow3 sensesSynonym of ouch (“cry of pain”).
• owe3 sensesTo be under an obligation to give something back to someone or to perform some action for someone.
• owed1 senseThat owes.
• Owen12 sensesA male given name. A male given name from Welsh, an anglicization of Welsh Owain.
• Owens6 sensesA surname transferred from the given name.
• owing1 senseStill to be paid; owed as a debt.
• owl6 sensesAny of various birds of prey of the order Strigiformes, families Strigidae and Tytonidae, that are primarily nocturnal and have forward-looking,…
• Owl1 senseA player or fan of Sheffield Wednesday Football Club.
• own19 sensesBelonging to; possessed; acquired and designated by; proper to; property of; titled to; held in one's name; under/using the name of. Often marks a…
• owned1 senseHaving an owner who is part of a specified group.
• owner2 sensesOne who owns something.
• ownership2 sensesThe state of having complete legal control of something; possession; proprietorship.
• ox2 sensesAn adult castrated male of cattle (B. taurus), especially when used as a beast of burden.
• Ox3 sensesA Chinese constellation located near Capricorn, one of the 28 lunar mansions and part of the larger Black Turtle.
• Oxford37 sensesA city and local government district in Oxfordshire, England, famous for its university.
• oxygen5 sensesThe chemical element (symbol O) with an atomic number of 8 and relative atomic mass of 15.9994. It is a colorless and odorless gas. Sometimes called…