Latin Derivatives
- O -


obliviosus, obliviosa, obliviosum - forgetful, unaware

oblivious - unmindful, unaware: Oblivious of their surroundings, the youngsters continued talking and laughing as they entered the temple. Also: oblivion (a state of being entirely forgotten), obliviousness, obliviscence (a forgetting). [oblivio, oblivionis, f. - forgetfulness, oblivion; obliviscor, oblivisci, oblitus sum - to forget] 

obliviscor, oblivisci, oblitus sum - to forget

oblivion - 1) condition or fact of being completely forgotten: Genealogies tend to postpone the oblivion that awaits most mortals. 2) the state of forgetting, Also: oblivious (unaware; forgetful), obliviousness. [oblivio, oblivionis, f. - oblivion, a being forgotten; forgetfulness; obliviosus, obliviosa, obliviosum - forgetful; oblivium, oblivi, n. - forgetfulness]

obscurus, obscura, obscurum - dark, covered, dim, indistinct

obscure - 1. unclear (to the eyes, the ears, or the mind): The president said he refused to sign the bill because of one obscure sentence. 2. unnoticeable; 3. dark. Also: obscurant (someone who tries to prevent the spread of knowledge), obscurantism (opposition to the spread of knowledge), obscurantist, obscuration (the act of obscuring; the condition of being obscured), obscureness, obscurer, obscurity (the state of being obscure). [obscuritas, obscuritatis, f. - darkness, indistinctness; obscuro, obscurare, obscuravi, obscuratus - to darken, cover] 

obsequor, obsequi, obsecutus sum - to comply with, obey

obsequies - funeral rites: The funeral cortege of a departed Hindu ends at the cremation ground, where the pyre is ignited by the deceased’s eldest son or grandson. Also: obsequious (servile obedience or deference), obsequiousness. [obsequentia, obsequentiae, f. - an inclination to please, agreeableness, complaisance; obsequium, obsequi, n. - compliance, submission; sequor, sequi, secutus - follow]

obsequious - characterized by servile compliance, fawningly obedient: Unaccustomed to being treated as royalty, the jackpot winners mistook the obsequious attention of their greedy neighbors for well-deserved respect. Also: obsequiousness. [obsequentia, obsequentiae, f. - inclination to please, agreeableness; obsequiosus, obsequiosa, obsequiosum - compliant; obsequium, obsequi, n. - compliance, submission] 

obstrepo, obstrepere, obstrepui, obstrepitus - to clamor at, roar at; to disturb by making noise

obstreperous - noisy, rough, and unruly: Only a few students are obstreperous, but many are quite talkative. Also: obstreperousness. [strepitus, strepitus, m. - a loud noise; strepo, strepere, strepui, strepitus - to make a loud noise] 

occulo, occulere, ocului, ocultus - to cover, hide, conceal

occult - (adj.) 1) hidden; secret; beyond human understanding; 2) pertaining to secret or "supernatural" arts such as magic, astrology, or alchemy: Some magicians delight in exploring occult phenomena in order to debunk them. (n.) secret or "supernatural" arts like magic and astrology considered as a whole; (v.) to block or hide from view. Also: occulter, occultness, occultation, ocultism (belief in occult agencies). [occultatio, occultationis f. - concealment, hiding; occulto, occultare, occultavi, occultatus - to hide, conceal; occultator, occultatoris, m. - a hider, concealer]

occupo, occupare, occupavi, occupatus - seize

preoccupied - absorbed in thought, lost in thought: She often seemed preoccupied; at those times, addressing her was like talking to a statue. Also: preoccupation, preoccupy (to fill the mind to the exclusion of other things). [praeoccupo, praeoccupare, praeoccupavi, praeoccupatus - take possession of beforehand; seize on beforehand] 

octo - eight

octogenarian - person in his or her eighties (between 80 and 89 years old): Octogenarians are commonplace in Okinawa, which has the highest life expectancy of any place in the world. [octogeni,octogenae, octogena - eighty at a time]

odium, odi, n. - hatred

odious - extremely displeasing, hateful (arousing hatred and deserving hatred), detestable: She had the odious habit of maligning others to make herself look good. Also: odiousness, odium (intense hatred). [odi, odisse, osurus (defective v.) - to hate; odiosus, odiosa, odiosum - hateful, offensive] 

officium, offici, n. - duty

officious - meddlesome; too ready to give advice; minding other people's business: Finally, when her officious secretary interrupted for the umpteenth time that day, she said, "If you'll do your work, I'll be able to do mine." Also: officiousness (quality or act of being officious). [officiosus, officiosa, officiosum - obliging, dutiful] 

omen, ominis, n. - an omen, a sign; a foreboding

abominate - to hate, abhor: Does anyone outside of Nepal really abominate the abominable snowman? Also: abomination, abominator. [ominor, ominari, ominatus sum - to presage, forebode; abominor, abominari, abominatus sum - to deprecate; to detest, abhor]

ominous - foreboding, threatening, portending evil: It is said that Caesar’s wife, Calpurnia, disquieted by ominous dreams, begged Caesar not to go to the Senate on the Ides of March. Also: omen (a sign of what will happen), ominousness. [ominor, ominari, ominatus sum - to forebode, presage, predict] 

omnis, omne - all, every

omnibus - 1) bus; 2) a volume of works by only one author or on only one subject: On his trip to Arizona, he bought an omnibus of mythological tales of the American Indians. 

omnifarious - of all kinds: She had a broad spectrum of interests and an insatiable curiosity; her journey through life can be described as omnifarious exploration. Also: omnifariousness. 

omniscience - knowing all things: Perhaps one has made some progress in the quest for wisdom when one realizes that he/she may be infinitely removed from omniscience. Also: omniscient (knowing all things). [scio, scire, scivi, scitus - to know; scientia, scientiae, f. - knowledge] 

omnivorous - 1) eating animals and plants; 2) intellectually taking in all kinds of things: Specialists concentrate most of their reading on one or several topics, whereas generalists tend to be omnivorous readers. Also: omnivore (an omnivorous person or animal), omnivorism, omnivorousness. [voro, vorare, voravi, voratus - to eat greedily]


onus, oneris, n. - load, burden

exonerate - to free from blame, clear of an accusation: Many a person has been exonerated posthumously, to which many a survivor has reacted with ambivalence, happy that a good name has been restored, sad that the restoration didn't come sooner. Also: exoneration, exonerative, exonerator. [exonero, exonerare, exoneravi, exoneratus - to unburden, free] 

opacus, opaca, opacum - shady, darkened

opaque - 1. not allowing light to pass through; not transparent or translucent: One can make a mirror by coating the back of a pane of glass with aluminum or silver, opaque substances that reflect light. 2. dark, dull; 3. hard to understand. Also: opaqueness. [opacitas, opacitatis, f. - shadiness; opaco, opacare, opacavi, opacatus - to shade] 

operio, operire, operui, opertus - to cover

covert - concealed, hidden, disguised, secret: Spying is a covert undertaking punishable in wartime by death. Also: covertness. [cooperio, cooperire, cooperui, coopertus - to cover completely] 

opinio, opinionis, f. - opinion, supposition

opine - to hold or express an opinion: As always when the Thanksgiving dinner was finished, the men opined they would watch a football game on TV, which meant they could be expected to nap for an hour or so. Also: opinion, opinionated, opinionatedness, opinionative, opinionativeness, opinioned. [opinatio, opinationis, f. - conjecture; opinator, opinatoris, m. - conjecturer; opinor, opinari, opinatus sum - to be of the opinion; to suppose, conjecture]

opportunus, opportuna, opportunum - fit, suitable

opportune - favorable, suitable: He had decided to wait for the opportune moment to ask his penurious boss for a raise; years later he was still waiting. Also: inopportune, opportuneness, opportunism (the policy of doing what is expedient regardless of its morality), opportunist, opportunistic, opportunity ) [opportunitas, opportunitatis, f. - fitness, suitableness]

oppugno, oppugnare, oppugnavi, oppugnatus - to attack

oppugn - 1) to oppose with criticism or argument: In political debate, propriety demands that one not oppugn one’s opponent, but his or her ideas. 2) to call into question. Also: oppugnant (opposing, contrary), oppugnancy, oppugner. [oppugnatio, oppugnationis, f. - an attack, assault; oppugnator, oppugnatoris, m. - an assailant]

optimus, optima, optimum - best

optimize - to make the most of; to get the most efficient use of: If you say, "One should optimize one's potential" when you mean, "You should do your best," you may be accused of using gobbledegook. Also: optimization, optimum (best), optimal (optimum). 

optimism - the tendency to look at the bright side of things and to expect the best: Intuitively one would say that there is a high positive correlation between optimism and longevity. Also: optimist, optimistic, optimistical. 

opulens, opultentis - wealthy

opulence - wealth, riches: Many think it a national disgrace that wealth and poverty, opulence and destitution, continue to exist side by side. Also: opulent, opulency. [opulentia, opulentiae, f. - wealth; opulentus, opulenta, opulentum - wealthy] 

oratio, orationis, f. - speech

oration - a formal public speech: She seems to think her every lecture is an oration. Also: orator (a person who speaks very well and with great eloquence in public; a person who delivers an oration), oratorical, oratorlike, oratory (the art of public speaking), oratrix (feminine form of “orator”). [orator, oratoris, m. - speaker; orator; oratorius, oratoria, oratorium - oratorical] 

orbis, orbis, m. - ring, circle

orbicular - rounded like a circle or sphere; ringlike; spherical: Unlike the planets, asteroids are not orbicular. Also: orb (sphere), orbless, orblike, orbicularness, orbicularity, orbiculate (orbicular), orbiculated (orbicular), orbiculation, orbit, orbital, orbiter.

orbita, orbitae, f. - rut, track made by a wheel

exorbitant - going beyond what is reasonable or proper in amount or extent; greatly excessive, extravagant: The price of some professional sports is exorbitant; I prefer to stay at home and watch games on television. Also: exorbitance, exorbitancy (exorbitance). 

ordino, ordinare, ordinavi, ordinatus - to set in order, arrange

inordinate - 1) excessive; much too great or too many; unrestrained: "Seek the via media," said the graduation speaker. "Inordinate virtue is a contradiction in terms." 2) not regulated. Also: inordinateness. 

ordain - 1) to establish as law; to decree; to order: According to Christians and Jews, the ten commandments are divinely ordained rules of conduct. 2) to consecrate as a clergyman; to invest with the office of a minister, priest, etc. Also: ordainable, ordainee (a person recently ordained), ordainer, ordainment, ordination (the ordaining of new clergy; the ceremony at which new clergy are ordained), preordain, preordination. 

ordinance - a rule or decree, especially one made by municipal and local authorities: Oldham County does not yet have an ordinance banning open burning. 

ordnance - military equipment, including weapons and ammunition. During World War II, many American factories established an ordnance division; for example, Servel (a gas refrigerator manufacturer) began making wings for the P48 fighter. 

origo, originis, f. - beginning, origin

aborigine - one of the earliest known inhabitants of a region: Much has been written about the injustices of the European invaders toward the aborigines of the American continents. Also: aboriginal (adj., pertaining to aborigines; original, native; n., aborigine), aboriginality.

oro, orare, oravi, oratus - to pray

inexorable - not influenced, persuaded, or moved by prayers or entreaties; unyielding: As he awaited the results of the biopsy, he was sure that the inexorable hand of death was resting on his shoulder. Also: inexorableness, inexorability. [inexorabilis, inexorabile - not able to be moved by entreaty] 

os, ossis, n. - bone

ossuary - a receptacle for the bones of the dead: A recently discovered ossuary, believed to be about 2000 years old, is inscribed with the words "James, son of Joseph, brother of Jesus." Also: ossuarium (ossuary). [osseus, ossea, osseum - of bone]

ostendo, ostendere, ostendi, ostentus - to show, display

ostensible - apparent (sometimes implying a concealment of the truth); professed: The ostensible reason for the delay is lack of cooperation. 

ostentatious - 1) done for display; pretentious: More often than not, the very wealthy deplore an ostentatious display of wealth. 2) habitually showing off. Also: ostentation, ostentatiousness. [ostento, ostentare, ostentavi, ostentatus - frequentative of ostendo) to show, display; to show off; ostentatio, ostentationis, f. - showing; showing off; pretence] 

otium, oti, n. - leisure

otiose - 1) lazy; idle: Behind her were the years of otiose attendance, of forgotten books, pencils, and paper; now she came to school each day with the desire to learn everything her teachers expected and more. 2) superfluous; useless. Also: otioseness, otiosity. [otiosus, otiosa, otiosum - at leisure, free from official business, free] 

Moutoux, Latin Derivatives 

Return to Latin Derivatives, page 1