obliquity
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C2 noun /əˈblɪkwɪti/

obliquity

obliquité
Meaning
Deviation from moral or usual conduct; indirectness or lack of straightforwardness.
Example
The politician was criticized for the obliquity of his answers.
Le politicien a été critiqué pour l'obliquité de ses réponses.
B2 noun /əˈfɛns/

offense

infraction
Meaning
an illegal act; a crime
Example
The offense was committed in broad daylight.
L'infraction a été commise en plein jour.
B2 verb /ˌoʊvərˈkʌm/

overcome

surmonter
Meaning
To succeed in dealing with a problem or difficulty.
Example
You can overcome procrastination with planning.
Vous pouvez surmonter la procrastination en planifiant.
C1 noun /ˈɔːr.ə.tɔːr.i/

oratory

art oratoire
Meaning
The art of public speaking; skilled and confident delivery of speeches to an audience.
Example
His exceptional oratory skills won him the debate competition.
Ses compétences exceptionnelles en oratoire lui ont permis de gagner la compétition de débat.
B2 verb /ˈɒkjʊpaɪ/

occupy

occuper
Meaning
to take up space or time; to live or work in a place
Example
The new family will occupy the house next month.
La nouvelle famille occupera la maison le mois prochain.
B1 noun /ˈɑp.ʃən/

Option

option
Meaning
a thing that is or may be chosen; an alternative course of action
Example
You have the option to work from home or office.
Vous avez l'option de travailler depuis chez vous ou au bureau.
B2 verb /ˌoʊvərˈpeɪ/

overpay

payer en trop
Meaning
To pay more than is necessary or reasonable.
Example
She realized she had overpaid for the concert tickets.
Elle s'est rendu compte qu'elle avait trop payé pour les billets de concert.
C1 adjective /ˈɑp.ər.ə.tɪv/

Operative

actif; en vigueur; fonctionnant; opérationnel;
Meaning
Functioning; in effect; working; active;
Example
The new safety protocols became operative immediately after the accident.
Les nouveaux protocoles de sécurité sont devenus opérationnels immédiatement après l'accident.
A2 adjective /ˈɑp.ə.zɪt/

Opposite

opposé; complètement différent; face à face; inverse;
Meaning
Contrary; completely different; facing each other; reverse;
Example
They have opposite views on politics but remain good friends.
Ils ont des vues opposées sur la politique mais restent de bons amis.
B2 noun /ˈɔːɡənɪzəm/

organism

organisme
Meaning
a living thing that has an organized structure and can grow and reproduce
Example
Every organism needs water to survive.
Chaque organisme a besoin d'eau pour survivre.
A1 adverb /ˈɔːfən/

often

souvent
Meaning
frequently, many times
Example
I often visit my grandparents on weekends.
Je visite souvent mes grands-parents le week-end.
B2 noun ˈaʊt.pʊt

output

production
Meaning
The amount of something produced by a person, machine, or industry.
Example
Climate change reduces agricultural output.
Le changement climatique réduit la production agricole.
C1 adjective /ˌɒmnɪˈprezənt/

omnipresent

omniprésent
Meaning
(of God) present everywhere at the same time.
Example
Social media has become an omnipresent force in modern society.
Les médias sociaux sont devenus une force omniprésente dans la société moderne.
C1 adjective /əˈbliːk/

Oblique

oblique; diagonal; indirect ou évasif
Meaning
slanting; diagonal; indirect or evasive
Example
The artist drew an oblique line across the canvas.
L'artiste a tracé une ligne oblique sur la toile.
B2 noun /əˈfens/

Offence

offense; délit; attaque
Meaning
a breach of law or rule; an annoyance or resentment
Example
Stealing is a serious offence punishable by law.
Le vol est une offense grave punissable par la loi.
C1 noun /ˈoʊvərˌtʊr/

overture

ouverture / proposition
Meaning
An introduction to something more substantial; a proposal or preliminary action.
Example
The peace overture was welcomed by both nations.
L'ouverture de la paix a été accueillie favorablement par les deux nations.
B1 noun /əˈkeɪ.ʒən/

Occasion

occasion; événement spécial
Meaning
a particular time or instance of an event; a special celebration
Example
Their wedding was a joyous occasion.
Leur mariage était une occasion joyeuse.
B1 noun /əˈpɪn.jən/

Opinion

opinion
Meaning
a view or judgment formed about something; a belief or assessment based on grounds short of proof
Example
In my opinion, this is the best solution.
À mon avis, c'est la meilleure solution.
B1 verb /ˈɔːrɡənaɪz/

organize

organiser
Meaning
to arrange systematically; to plan and coordinate
Example
She organized a surprise party for her friend.
Elle a organisé une fête surprise pour son amie.
A1 adjective /oʊld/

old

vieux
Meaning
having lived for a long time; not new or young
Example
He still drives his old car.
Il conduit toujours sa vieille voiture.
C2 noun /ˈoʊpiət/

opiate

opiacé
Meaning
a drug containing opium or its derivatives, used to relieve pain or cause sleep
Example
The doctor prescribed an opiate to relieve the patient's pain.
Le docteur a prescrit un opiacé pour soulager la douleur du patient.
C1 noun ˈaʊt.sɔːr.sɪŋ

outsourcing

externalisation
Meaning
The practice of having certain job functions done outside a company instead of having an in-house department or employee handle them.
Example
Many companies use outsourcing to reduce labor costs.
De nombreuses entreprises utilisent l'externalisation pour réduire les coûts de main-d'œuvre.
C2 noun /ɒmˈnɪʃəns/

omniscience

omniscience
Meaning
the state of knowing everything
Example
The novel's narrator has an air of omniscience, revealing every character's thoughts.
Le narrateur du roman a un air d'omniscience, révélant les pensées de chaque personnage.
C1 adjective /ˌɒstɛnˈteɪʃəs/

ostentatious

ostentatoire
Meaning
Characterized by a showy or pretentious display intended to impress others.
Example
He wore an ostentatious gold chain to the party.
Il portait une chaîne en or ostentatoire à la fête.
B2 noun /ˈɒfərɪŋ/

offering

offre
Meaning
something that is given, especially as a gift or contribution
Example
The company’s latest offering is an eco-friendly car.
La dernière offre de l'entreprise est une voiture écologique.
C1 noun /ˈɒstrəsɪzəm/

ostracism

ostracisme
Meaning
The act of excluding someone from a group or society.
Example
The student faced ostracism after breaking the rules.
L'étudiant a fait face à l'ostracisme après avoir enfreint les règles.
C1 adjective /əbˈstrʌk.tɪv/

Obstructive

obstructif
Meaning
deliberately creating difficulties or preventing progress; hindering or blocking something
Example
The obstructive policies hindered economic growth.
Les politiques obstructives ont entravé la croissance économique.
C1 adjective /ˌaʊt əv ðə ˈweɪ/

out-of-the-way

éloigné ou inhabituel
Meaning
remote or unusual; not in a convenient or usual location
Example
They stayed in an out-of-the-way village.
Ils sont restés dans un village éloigné.
B2 adjective /ˈɔː.də.li/

Orderly

ordonné; systématique; pacifique
Meaning
well-organized; systematic; peaceful
Example
Please keep your desk orderly and clean.
Veuillez garder votre bureau ordonné et propre.
B1 adjective, adverb /ˈoʊvərɔːl/

overall

dans l'ensemble
Meaning
in general or as a whole
Example
Overall, the project has been successful.
Dans l'ensemble, le projet a été un succès.
C1 noun /oʊˈbɪt.ʃu.er.i/

Obituary

nécrologie
Meaning
a notice of someone's death published in a newspaper; biographical account of deceased person
Example
The newspaper published his obituary yesterday.
Le journal a publié son nécrologie hier.
A2 noun /ˈoʊ.ʃən/

ocean

océan
Meaning
A very large expanse of sea, especially the main areas of sea between continents.
Example
The ocean covers more than 70% of the Earth's surface.
L'océan couvre plus de 70% de la surface de la Terre.
B2 noun /ˈɔːɡən/

organ

organe
Meaning
a part of the body that performs a specific function
Example
The heart is an important organ in the human body.
Le cœur est un organe important dans le corps humain.
C1 noun /ˈɒktəɡən/

octagon

octogone
Meaning
A polygon with eight sides and eight angles.
Example
The stop sign is shaped like an octagon.
Le panneau stop a la forme d'un octogone.
C1 noun /ˌɑːk.sɪˈmɔːr.ɒn/

oxymoron

oxymore
Meaning
a figure of speech where two contradictory terms are combined
Example
The phrase 'deafening silence' is a classic oxymoron.
L'expression 'silence assourdissant' est un oxymore classique.
B2 adjective /əˈfen.sɪv/

Offensive

offensant; insultant; agressif
Meaning
causing displeasure or resentment; insulting; aggressive
Example
His offensive remarks hurt everyone's feelings.
Ses remarques offensantes ont blessé les sentiments de tout le monde.
C1 noun /ˈɔɪntmənt/

ointment

onguent
Meaning
A smooth, oily substance applied to the skin for healing or soothing.
Example
The doctor prescribed an ointment for the burn on his arm.
Le médecin a prescrit un onguent pour la brûlure sur son bras.
C1 noun əˈblɪv.i.ən

oblivion

oubli, destruction, disparition
Meaning
The state of being unaware or unconscious of what is happening; complete forgetfulness.
Example
His name faded into oblivion over time.
Son nom s'est effacé dans l'oubli au fil du temps.
C2 noun /ˈɒrɪz(ə)n/

orison

prière
Meaning
a prayer, especially a devout or formal one
Example
He whispered a quiet orison before going to sleep.
Il murmura une prière silencieuse avant de dormir.
C2 noun ˈoʊʃən ˌstrætɪfɪˈkeɪʃən

ocean stratification

stratification océanique
Meaning
The formation of layers in ocean water due to differences in density.
Example
Ocean stratification affects marine biodiversity.
La stratification océanique affecte la biodiversité marine.
A2 noun /ˈɒpərə/

opera

opéra
Meaning
a dramatic performance in which the actors sing most of their lines
Example
We watched a beautiful opera at the theater last night.
Nous avons regardé un bel opéra au théâtre hier soir.
B2 verb /ˌoʊvərˈtɜrn/

overturn

renverser / annuler une décision
Meaning
to turn something upside down or to reverse a decision or judgment
Example
The court decided to overturn the previous ruling.
Le tribunal a décidé d'annuler la décision précédente.
C1 adjective ˈɒptɪmaɪzd

optimized

optimisé, amélioré, plus efficace
Meaning
Made as fully perfect, functional, or effective as possible; improved to achieve maximum efficiency.
Example
The system has been optimized for faster performance.
Le système a été optimisé pour des performances plus rapides.
A2 pronoun /aʊərˈsɛlvz/

ourselves

nous-mêmes
Meaning
used by the speaker to refer to themselves and one or more others as the object of the verb
Example
We should help ourselves before helping others.
Nous devons nous aider nous-mêmes avant d'aider les autres.
C2 noun /oʊliˈændər/

Oleander

oléandre
Meaning
a poisonous evergreen shrub with clusters of white, pink, or red flowers
Example
The beautiful oleander flowers bloomed in the garden despite their toxic nature.
Les belles fleurs d'oléanre ont fleuri dans le jardin malgré leur nature toxique.
B2 noun /əbˈdʒek.ʃən/

Objection

objection; désaccord; protestation;
Meaning
an expression of disagreement or disapproval; a reason for disagreeing
Example
The lawyer raised an objection during the trial.
L'avocat a soulevé une objection pendant le procès.
C1 adjective /ɔːˈneɪt/

ornate

orné
Meaning
elaborately or highly decorated
Example
The palace hall was filled with ornate furniture and paintings.
La salle du palais était remplie de meubles ornés et de peintures.
C1 adjective /əˈblɪɡ.ə.tɔː.ri/

obligatory

obligatoire
Meaning
Required by a legal, moral, or other rule; compulsory.
Example
Wearing a seatbelt is obligatory in most countries.
Porter une ceinture de sécurité est obligatoire dans la plupart des pays.
C1 verb /ˌoʊvərˈpaʊər/

overpower

dominer
Meaning
To defeat or gain control over someone or something by using greater strength or force.
Example
The soldiers managed to overpower the enemy forces.
Les soldats ont réussi à dominer les forces ennemies.
C2 verb /ˈɑːbdʒərˌɡeɪt/

objurgate

réprimander sévèrement
Meaning
to scold or rebuke severely
Example
The teacher objurgated the student for being dishonest.
Le professeur a réprimandé sévèrement l'élève pour son malhonnêteté.
C1 noun /ˈɒf.sprɪŋ/

offspring

progéniture
Meaning
a person's child or children; an animal's young
Example
The bird carefully fed its offspring.
L'oiseau a nourri soigneusement sa progéniture.
B2 noun /ˈaʊt.breɪk/

Out-break

épidémie
Meaning
a sudden occurrence or eruption of something, especially disease or violence
Example
The outbreak of flu affected many students in the school.
L'épidémie de grippe a touché de nombreux élèves à l'école.
B2 noun ˈɔː.bɪt

orbit

orbite
Meaning
The curved path of a celestial object around a star, planet, or moon.
Example
The satellite maintains its orbit around Earth.
Le satellite maintient son orbite autour de la Terre.
B2 noun /ˈaʊtlet/

outlet

sortie
Meaning
a means by which something is released, expressed, or distributed
Example
Art is a great outlet for emotions.
L'art est une excellente sortie pour les émotions.
C1 adjective /ˌəʊ.vərˈɑː.tʃɪŋ/

overarching

global, englobant, tout-en-un
Meaning
Comprehensive or all-embracing; forming an arch over something.
Example
The overarching theme of the book is human resilience.
Le thème global du livre est la résilience humaine.
A2 modal verb /ɔːt/

ought

devrait
Meaning
Used to indicate duty, correctness, or moral obligation.
Example
You ought to respect your elders.
Tu devrais respecter tes aînés.
C1 verb /ˈɔːstrəˌsaɪz/

ostracize

ostraciser
Meaning
to exclude someone from a group or society; to banish or shun
Example
After the scandal, he was ostracized by his former colleagues.
Après le scandale, il a été ostracisé par ses anciens collègues.
B2 noun /ˌɔː.ri.enˈteɪ.ʃən/

orientation

orientation
Meaning
the process of becoming familiar with a new situation or environment
Example
The company provides an orientation for all new employees.
L'entreprise offre une orientation à tous les nouveaux employés.
C1 noun /ˈaʊtpoʊst/

outpost

avant-poste
Meaning
A small military camp or position at some distance from the main force, used especially as a guard.
Example
The soldiers were stationed at a remote outpost.
Les soldats étaient stationnés dans un avant-poste éloigné.
C1 noun /ˈɒktɪv/

octave

octave
Meaning
A series of eight musical notes, or the interval between one musical pitch and another with double its frequency.
Example
The singer's voice could easily reach the higher octave.
La voix du chanteur pourrait facilement atteindre l'octave supérieure.
C1 noun /ˌɑːsɪˈleɪʃən/

oscillation

oscillation
Meaning
The movement back and forth at a regular speed.
Example
The oscillation of the pendulum controls the clock.
L'oscillation du pendule contrôle l'horloge.
B1 verb /əbˈzɜːrv/

observe

observer
Meaning
to watch carefully; to notice or perceive something
Example
Scientists observe the behavior of animals in the wild.
Les scientifiques observent le comportement des animaux dans la nature.
C2 verb /ˈɑːskjʊleɪt/

osculate

embrasser
Meaning
To kiss.
Example
They osculated under the mistletoe during the party.
Ils se sont embrassés sous le gui pendant la fête.
C2 adjective /ɒmˈnɪʃ.ənt/

Omniscient

omniscient
Meaning
having complete knowledge; all-knowing
Example
The narrator in the novel appears to be omniscient, knowing every character's thoughts.
Le narrateur dans le roman semble être omniscient, connaissant toutes les pensées des personnages.
C2 adjective /ˈɑːsɪˌfaɪd/

ossified

transformé en os, rigide
Meaning
Turned into bone or become rigid; unwilling to change.
Example
The company had an ossified management structure that resisted innovation.
L'entreprise avait une structure de gestion rigide qui résistait à l'innovation.
B2 adjective + noun ˈɒptɪməl ˈtempərətʃər

optimal temperature

température optimale
Meaning
The best or most favorable temperature for a particular purpose
Example
Winter provides optimal temperature for farming.
L'hiver fournit la température optimale pour l'agriculture.
C1 adjective əˈblɪv.i.əs

oblivious

ignorant
Meaning
Being completely unaware of surrounding events.
Example
He was oblivious to the noise around him while reading.
Il était inconscient du bruit autour de lui en lisant.
C2 noun /ˈɔɪl.mən/

Oilman

pétrolier
Meaning
a person who works in the oil industry; someone who sells oil or petroleum products
Example
The oilman discovered a new oil field in the desert.
Le pétrolier a découvert un nouveau champ pétrolier dans le désert.
B2 noun /oʊˈbiː.di.əns/

Obedience

obéissance
Meaning
compliance with an order, request, or law; submission to authority
Example
Children should show obedience to their parents.
Les enfants doivent montrer de l'obéissance envers leurs parents.
A2 noun /ɔɪl/

Oil

huile
Meaning
a viscous liquid derived from petroleum or plants, used for cooking or fuel
Example
Heat the oil in a pan before adding the vegetables.
Chauffez l'huile dans une poêle avant d'ajouter les légumes.
B2 noun /əˌrɪʒ.əˈnæl.ə.ti/

Originality

originalité
Meaning
the quality of being novel or unusual; the ability to think independently and creatively
Example
The artist's work showed great originality and creativity.
Le travail de l'artiste a montré une grande originalité et créativité.
C1 adjective /ˈɔːrθədɑːks/

orthodox

orthodoxe
Meaning
conforming to traditional beliefs or practices
Example
He comes from a very orthodox family.
Il vient d'une famille très orthodoxe.
C2 adjective /əbˈsiːkwɪəs/

obsequious

servile
Meaning
Excessively obedient or attentive in a servile way.
Example
The waiter gave an obsequious bow to every customer.
Le serveur fit une révérence servile à chaque client.
B2 noun /ˈaʊtlʊk/

outlook

perspective, prévision
Meaning
a person's general attitude or view; a forecast or prospect
Example
The economic outlook for the year is positive.
Les prévisions économiques pour l'année sont positives.
A1 adjective /ˈʌðər/

other

autre
Meaning
used to refer to something different from the one already mentioned or known
Example
I don't want this one, I will take the other one.
Je ne veux pas de celui-ci, je prendrai l'autre.
C2 adjective /ˈɒf.biːt/

offbeat

inhabituel
Meaning
Unusual, unconventional, or different from the norm.
Example
She has a very offbeat sense of humor.
Elle a un sens de l'humour très inhabituel.
B2 adjective; verb (past participle) /ˈɒkjʊpaɪd/

occupied

occupé
Meaning
being in use or taken; filled or lived in; controlled or held by force
Example
The room is occupied, so please wait outside.
La chambre est occupée, veuillez attendre dehors.
C2 noun /ˌɒpəˈrɛtə/

operetta

opéra léger
Meaning
a short opera with light and humorous themes
Example
The theater staged a famous operetta by Gilbert and Sullivan.
Le théâtre a présenté une célèbre opérette de Gilbert et Sullivan.
C1 adjective /ˌaʊt ən ˈaʊt/

out-and-out

complet
Meaning
complete; absolute; used to emphasize something extreme
Example
The speech was an out-and-out lie.
Le discours était un mensonge complet.
C1 noun /ˈaʊtriːtʃ/

outreach

expansion de l'aide
Meaning
The act of providing services or support to people who might not otherwise have access to them.
Example
The charity launched a new outreach program for the homeless.
L'association a lancé un nouveau programme d'expansion de l'aide pour les sans-abri.
C1 adjective /əbˈnɒkʃəs/

Obnoxious

odieux
Meaning
extremely unpleasant; offensive; annoying
Example
His obnoxious behavior at the party annoyed everyone.
Son comportement odieux à la fête a agacé tout le monde.
C1 verb /ˈɒs.ɪ.leɪt/

oscillate

se balancer ou se déplacer d'un point à un autre entre deux états
Meaning
To swing or move back and forth between two points or states
Example
The stock market tends to oscillate during uncertain times.
Le marché boursier a tendance à osciller pendant les périodes incertaines.
C2 noun /ˈoʊdiəm/

odium

odium
Meaning
general or widespread hatred or disgust directed toward someone as a result of their actions
Example
The scandal brought public odium on the corrupt minister.
Le scandale a attiré l'odium public sur le ministre corrompu.
C2 noun /oʊˈbeɪsəns/

obeisance

révérence
Meaning
A gesture of respect such as a bow or curtsy.
Example
They bowed in obeisance to the king.
Ils se sont inclinés en révérence au roi.
B2 noun ɔːˈɡæn.ɪk fuːdz

organic foods

aliments biologiques
Meaning
Food produced without the use of chemicals such as artificial pesticides, fertilizers, or other artificial agents.
Example
Organic foods are healthier than processed foods.
Les aliments biologiques sont plus sains que les aliments transformés.
C2 adjective /ˌɔːfˈkiː/

off-key

fausse note
Meaning
out of tune; not in accordance with expected standards
Example
The singer was slightly off-key during the performance.
Le chanteur était légèrement hors de ton pendant la performance.
A1 preposition /ʌv/

of

de
Meaning
expressing the relationship between a part and a whole
Example
The book is on the table, in front of the window.
Le livre est sur la table, devant la fenêtre.
B2 adjective /ˌɔːɡənaɪˈzeɪʃənəl/

organizational

organisationnel
Meaning
relating to the structure or arrangement of a company or group
Example
He works on improving the organizational structure of the company.
Il travaille à améliorer la structure organisationnelle de l'entreprise.
C2 verb /ˌaʊtməˈnuːvər/

outmaneuver

surpasser habilement
Meaning
to gain an advantage over an opponent by skillful or clever action
Example
The smaller company managed to outmaneuver its larger rival.
La petite entreprise a réussi à surpasser habilement son grand concurrent.
C1 adjective /əˈprɛs.ɪv/

Oppressive

oppressif
Meaning
Harsh and authoritarian; overwhelming; causing distress; tyrannical;
Example
The oppressive heat made it difficult to work outside during the summer.
La chaleur oppressante rendait difficile de travailler à l'extérieur pendant l'été.
C1 adjective/adverb /ˌɒfˈhænd/

offhand

sans réflexion
Meaning
Without previous thought or preparation; casual and sometimes dismissive.
Example
She gave an offhand reply to his serious question.
Elle a donné une réponse sans réfléchir à sa question sérieuse.
C1 verb /ˈɒp.tɪ.maɪz/

optimize

optimiser
Meaning
To make the best or most effective use of a situation, opportunity, or resource.
Example
The company is working to optimize its supply chain.
L'entreprise travaille à optimiser sa chaîne d'approvisionnement.
B2 noun /ˈaʊtɪŋ/

outing

excursion
Meaning
a short trip or excursion, often for leisure or enjoyment
Example
They had a lovely outing at the beach last weekend.
Ils ont fait une belle excursion à la plage le week-end dernier.
C1 noun /ˈɑn.set/

Onset

début; commencement
Meaning
the beginning or early stages of something; the start of a medical condition
Example
The onset of winter brought heavy snowfall.
Le début de l'hiver a apporté de fortes chutes de neige.
C1 adjective /ˈɔːrdɪnəl/

ordinal

ordinal
Meaning
Relating to the order or position of something in a sequence (first, second, third, etc.).
Example
The ordinal number 'third' indicates position in a sequence.
Le numéro ordinal 'troisième' indique la position dans une séquence.
B2 verb /ˌoʊvərˈsiː/

oversee

superviser
Meaning
to supervise or watch over something; to manage and direct
Example
The manager will oversee the entire construction project.
Le gestionnaire supervisera l'ensemble du projet de construction.
C1 verb /aʊtˈlɪv/

outlive

survivre
Meaning
to live longer than someone or something else
Example
She outlived all her siblings.
Elle a vécu plus longtemps que tous ses frères et sœurs.
A1 adjective/adverb /ˈoʊnli/

only

seul
Meaning
without others; solely
Example
He is the only person who knows the secret.
Il est la seule personne qui connaît le secret.
C1 adjective /əˈblaɪdʒɪŋ/

obliging

serviable
Meaning
Willing to help or do favors; accommodating.
Example
The staff at the hotel were very obliging and friendly.
Le personnel de l'hôtel était très serviable et amical.
C2 adjective /ɔːrˈθɑːɡənl/

orthogonal

orthogonal
Meaning
at right angles; independent or unrelated
Example
In mathematics, two vectors are orthogonal if their dot product is zero.
En mathématiques, deux vecteurs sont orthogonaux si leur produit scalaire est nul.
C1 noun /ˌɑːpərˈtuːnɪst/

opportunist

opportuniste
Meaning
A person who takes advantage of situations for personal gain, often disregarding principles.
Example
He is seen as an opportunist who always puts his interests first.
Il est vu comme un opportuniste qui met toujours ses intérêts en premier.
C2 noun /ˈɔːrdʒi/

orgy

orgie
Meaning
A wild party involving excessive indulgence, especially of a sexual nature.
Example
The novel described a scandalous orgy in a wealthy mansion.
Le roman a décrit une orgie scandaleuse dans un manoir riche.
A2 adjective/adverb /ˈɒnˌlaɪn/

online

en ligne
Meaning
connected to or available through the internet
Example
I prefer shopping online rather than going to stores.
Je préfère faire du shopping en ligne plutôt que d'aller dans les magasins.
C1 adjective ˈɒb.stɪ.nət

obstinate

obstiné
Meaning
Refusing to change one's mind or accept others' advice easily.
Example
He remained obstinate despite the logical arguments.
Il est resté obstiné malgré les arguments logiques.
B1 adjective /ˌoʊld ˈfæʃənd/

old-fashioned

démodé
Meaning
not modern; belonging to an earlier time
Example
He still wears an old-fashioned hat.
Il porte encore un chapeau démodé.
B2 noun/verb /ˌoʊvərˈlæp/

overlap

chevauchement
Meaning
To extend over and cover partly; an area where things coincide.
Example
The two meetings overlap by an hour.
Les deux réunions se chevauchent d'une heure.
C2 noun /ˈɑːbəlɪsk/

obelisk

obélisque
Meaning
A tall, four-sided, narrow tapering monument with a pyramid-shaped top.
Example
The ancient Egyptians built obelisks to honor their gods.
Les anciens Égyptiens ont construit des obélisques pour honorer leurs dieux.
C1 adjective /ˈɒm.ɪ.nəs/

Ominous

menaçant; sinistre
Meaning
giving the impression that something bad will happen; threatening; foreboding
Example
The dark clouds looked ominous before the storm.
Les nuages sombres paraissaient menaçants avant la tempête.
B2 noun ˈɒksɪdʒən prəˈdʌkʃən

oxygen production

production d'oxygène
Meaning
The process of generating oxygen through photosynthesis or other means.
Example
Plants are vital for oxygen production and the maintenance of life.
Les plantes sont vitales pour la production d'oxygène et le maintien de la vie.
C1 noun /ɒpˈtɒmɪtrɪst/

optometrist

optométriste
Meaning
A healthcare professional who examines eyes and prescribes corrective lenses.
Example
The optometrist prescribed new glasses for her.
L'optométriste a prescrit de nouvelles lunettes pour elle.
C1 adjective /ˈəʊnərəs/

onerous

ardu
Meaning
involving a great deal of effort, difficulty, or burden
Example
Fulfilling the contract proved to be an onerous task for the company.
Accomplir le contrat s'est avéré être une tâche ardue pour l'entreprise.
C1 verb /ɔːrˈdeɪn/

ordain

ordonner
Meaning
To officially make someone a priest or minister; to decree or order something officially.
Example
The bishop will ordain three new priests this Sunday.
L'évêque ordonnera trois nouveaux prêtres ce dimanche.
C1 verb /ˌoʊvərˈruːl/

overrule

rejeter
Meaning
to reject or disallow by exercising one's superior authority; to override a decision
Example
The judge overruled the objection from the defense attorney.
Le juge a rejeté l'objection de l'avocat de la défense.
A2 noun /ˈɒbdʒɪkt/

object

objet
Meaning
a thing that can be seen and touched
Example
The table is an object in the room.
La table est un objet dans la pièce.
C1 noun /əˈkɜr.əns/

Occurrence

événement
Meaning
an instance or event of something happening; the fact of occurring
Example
The occurrence of earthquakes is common in this region.
L'occurrence des tremblements de terre est courante dans cette région.
C1 noun /ˈɔːrkɪd/

Orchid

orchidée
Meaning
a diverse family of flowering plants known for their exotic and often fragrant flowers
Example
The white orchid on the windowsill bloomed for months.
L'orchidée blanche sur le rebord de la fenêtre a fleuri pendant des mois.
B1 noun /ˈɔr.ə.ʒɪn/

Origin

origine
Meaning
the point or place where something begins, arises, or is derived; the source
Example
Scientists are studying the origin of the universe.
Les scientifiques étudient l'origine de l'univers.
C1 adjective /ˈɒptɪkəl/

optical

optique
Meaning
related to or used in seeing or sight
Example
The optical illusion fooled everyone at the exhibition.
L'illusion optique a trompé tout le monde lors de l'exposition.
B2 noun /əˈpoʊ.nənt/

Opponent

opposant; rival
Meaning
a person who disagrees with or resists a proposal or practice; someone who competes against another
Example
The chess player defeated his strongest opponent.
Le joueur d'échecs a battu son plus fort opposant.
C2 verb /ˈɔːreɪt/

orate

prêcher
Meaning
To speak in a formal, often pompous manner
Example
He began to orate at the ceremony.
Il a commencé à prêcher lors de la cérémonie.
B2 noun /ˌɑb.lɪˈɡeɪ.ʃən/

Obligation

obligation
Meaning
a duty or commitment; something that must be done legally or morally
Example
Parents have an obligation to care for their children.
Les parents ont l'obligation de prendre soin de leurs enfants.