oscillation
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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.
C1 adjective /oʊˈvɜːrt/

overt

ouvert
Meaning
Done or shown openly; not hidden or secret.
Example
There was an overt display of hostility between the rivals.
Il y avait une démonstration ouverte d'hostilité entre les rivaux.
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 /ˈɑː.lɪv/

Olive

olive
Meaning
a small oval fruit with a hard pit, typically green or black, used for eating or making oil
Example
Olive oil is considered one of the healthiest cooking oils available.
L'huile d'olive est considérée comme l'une des huiles de cuisson les plus saines disponibles.
C2 noun /ˈɒfərtɔːri/

offertory

offrande
Meaning
The part of a religious service when offerings are collected; the offering itself.
Example
The offertory was taken during the Sunday service.
L'offrande a été prise pendant le service du dimanche.
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/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.
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.
A2 adjective /əˈlɪmpɪk/

olympic

olympique
Meaning
related to the Olympic Games, a major international sporting event
Example
She trained hard to compete in the Olympic Games.
Elle a beaucoup travaillé pour participer aux Jeux Olympiques.
C1 noun /ˌɒbstəˈtrɪʃən/

obstetrician

obstétricien
Meaning
A doctor specializing in pregnancy, childbirth, and women's reproductive health.
Example
The obstetrician monitored the mother’s health throughout the pregnancy.
L'obstétricien a surveillé la santé de la mère tout au long de la grossesse.
C1 adjective /ˈɒptɪk/

optic

optique
Meaning
Relating to the eye or vision.
Example
The optic nerve carries signals from the eye to the brain.
Le nerf optique transporte les signaux de l'œil au cerveau.
A2 noun /ˈɒf.ɪs/

office

bureau
Meaning
a room or building where people work, usually at desks
Example
She left the office early to attend a family event.
Elle a quitté le bureau tôt pour assister à un événement familial.
C2 verb /ˈoʊɡəl/

ogle

regarder avec désir
Meaning
To look at someone with obvious sexual interest.
Example
He kept ogling the models on the runway.
Il n'arrêtait pas de regarder les mannequins sur le podium.
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.
C2 noun ˈɒpjʊləns

opulence

opulence
Meaning
Great wealth or luxuriousness.
Example
The opulence of the mansion was evident in its ornate furnishings.
L'opulence du manoir était évidente dans ses meubles ornés.
C1 adverb /ˈɒp.tɪ.məl.i/

optimally

de manière optimale
Meaning
In the most effective or efficient way possible.
Example
Tasks should be allocated optimally for maximum output.
Les tâches doivent être attribuées de manière optimale pour un rendement maximal.
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.
A2 adjective /ˈɒb.vi.əs/

Obvious

évident; facile à comprendre
Meaning
easily perceived or understood; clear and apparent to the mind
Example
It was obvious that she was upset about something.
Il était évident qu'elle était contrariée à propos de quelque chose.
B2 adjective /ˌfæʃ.ənd/

Outdated

obsolète
Meaning
obsolete; no longer current
Example
This computer software is completely outdated.
Ce logiciel informatique est complètement obsolète.
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.
B2 adjective /ˈɒp.tɪ.məl/

optimal

optimal, le plus favorable
Meaning
Best or most favorable; the most effective under particular conditions.
Example
The optimal temperature for plant growth is around 25°C.
La température optimale pour la croissance des plantes est d'environ 25°C.
C2 noun /ˈoʊvərlɔːrd/

overlord

seigneur
Meaning
A ruler, master, or person of great power and authority over others.
Example
The peasants were forced to pay taxes to their overlord.
Les paysans ont été forcés de payer des impôts à leur seigneur.
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 noun /ˈɔːrnəmənt/

ornament

ornement
Meaning
A decorative object that adds beauty to something.
Example
The Christmas tree was decorated with colorful ornaments.
L'arbre de Noël était décoré avec des ornements colorés.
A2 noun /ˈʌn.jən/

Onion

oignon
Meaning
a round vegetable with a strong taste and smell, made up of many layers
Example
I need to chop some onions for the curry recipe.
J'ai besoin de couper des oignons pour la recette du curry.
A2 preposition /ˈɒntu/

onto

sur
Meaning
moving to a position on the surface of something
Example
She jumped onto the table to get the book.
Elle a sauté sur la table pour prendre le livre.
C1 adjective /ɒˈstɛnsəbl/

ostensible

apparente
Meaning
stated or appearing to be true, but not necessarily so
Example
His ostensible reason for leaving was illness, but many doubted it.
Sa raison apparente de partir était la maladie, mais beaucoup en doutaient.
B2 adjective /ˈɔɪl.i/

Oily

huileux; recouvert d'huile; gras
Meaning
covered with oil; containing oil; greasy
Example
Her oily skin needs special care.
Sa peau huileuse a besoin de soins spéciaux.
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.
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.
B1 noun ˌɔː.ɡən.aɪˈzeɪ.ʃən

organization

organisation
Meaning
An organized group of people with a particular purpose, such as a business or government department.
Example
The organization was officially inaugurated in 2024.
L'organisation a été inaugurée officiellement en 2024.
B2 adverb /ˈaʊtraɪt/

Outright

directement; complètement; sans réserve
Meaning
completely; directly; without reservation or concealment
Example
She rejected the proposal outright.
Elle a rejeté la proposition directement.
C1 adjective /ˈaʊt.kɑːst/

Outcast

rejeté
Meaning
rejected by society; excluded person
Example
He felt like an outcast in his new school.
Il s'est senti comme un rejeté dans sa nouvelle école.
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.
C2 noun /ˈɒb.stɪ.nə.si/

obstinacy

obstination
Meaning
Stubborn refusal to change one's opinion or chosen course of action, despite attempts to persuade one to do so.
Example
His obstinacy made negotiations difficult.
Son obstination a rendu les négociations difficiles.
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.
B2 noun /ˈɒkjʊpənt/

occupant

occupant
Meaning
A person who resides in or is present in a house, vehicle, seat, or place.
Example
The car had three occupants at the time of the accident.
La voiture avait trois occupants au moment de l'accident.
B2 noun /ˌoʊ.vɚˈkraʊ.dɪŋ/

overcrowding

surpeuplement excessif
Meaning
Excessive crowd or packed condition, having more people or vehicles in a place than the approved capacity.
Example
The subway system suffers from severe overcrowding during peak hours.
Le système de métro souffre de grave surpeuplement pendant les heures de pointe.
B1 noun /ˈɔːfɪsər/

officer

officier
Meaning
a person in a position of authority, especially in law enforcement
Example
The officer gave him a ticket for speeding.
L'officier lui a donné une amende pour excès de vitesse.
B2 adverb /ˈəʊvəli/

overly

excessivement
Meaning
to an excessive degree or extent
Example
She was overly concerned about the results.
Elle était excessivement préoccupée par les résultats.
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 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.
C1 adjective /aʊtˈmoʊdɪd/

outmoded

démodé
Meaning
No longer in fashion or useful; outdated.
Example
That old computer is completely outmoded.
Cet ancien ordinateur est complètement démodé.
C1 adjective /ˌɔːrnəˈmɛntl/

ornamental

ornemental
Meaning
Serving as decoration; decorative rather than functional.
Example
The garden was filled with ornamental plants.
Le jardin était rempli de plantes ornementales.
C1 adjective /ˌɔːrθəˈpiːdɪk/

orthopedic

relatif à la correction des déformations osseuses ou musculaires
Meaning
Relating to the correction of deformities of bones or muscles.
Example
She visited an orthopedic surgeon for her back pain.
Elle a consulté un chirurgien orthopédique pour sa douleur au dos.
B2 noun /ˈɔɪ.stər/

Oyster

huître
Meaning
a type of shellfish that can be eaten and sometimes contains pearls
Example
She ordered fresh oysters at the seafood restaurant.
Elle a commandé des huîtres fraîches au restaurant de fruits de mer.
C2 adjective /əˈprəʊ.bri.əs/

opprobrious

désobligeant
Meaning
Expressing strong criticism or scorn.
Example
He made opprobrious remarks about his opponent.
Il a fait des remarques désobligeantes sur son adversaire.
C1 verb /ˌoʊvərˈriːtʃ/

overreach

dépassement de soi
Meaning
to go beyond what is proper, acceptable, or achievable; to overextend
Example
The politician overreached by making promises he couldn't keep.
Le politicien a dépassé les limites en faisant des promesses qu'il n'a pas pu tenir.
C2 verb /əˈkluːd/

occlude

obstruer
Meaning
To block or close up an opening or passage.
Example
The pipe was occluded by mineral deposits.
Le tuyau était obstrué par des dépôts minéraux.
A2 adverb; noun /ˌaʊtˈdɔːrz/

outdoors

à l’extérieur
Meaning
outside a building; the natural environment outside
Example
We spent the whole afternoon outdoors enjoying the fresh air.
Nous avons passé tout l’après-midi à l’extérieur à profiter de l’air frais.
B2 noun /ˈaʊtskɜːrts/

outskirts

périphérie de la ville
Meaning
The outer parts of a town or city, away from the center.
Example
They moved to the outskirts of the city for a quieter life.
Ils ont déménagé en périphérie de la ville pour une vie plus calme.
A2 adjective /ˈɔː.dɪ.nər.i/

Ordinary

ordinaire; normal; pas spécial
Meaning
normal; usual; not special
Example
It was just an ordinary day at the office.
C'était juste un jour ordinaire au bureau.
B1 adjective /əˈkeɪ.ʒən.əl/

Occasional

occasionnel
Meaning
occurring infrequently or irregularly; happening from time to time
Example
She enjoys occasional walks in the park.
Elle aime les promenades occasionnelles dans le parc.
B1 noun əbˈdʒek.tɪv

objective

objectif
Meaning
A thing aimed at or sought; a goal.
Example
The main objective is to test sustainability.
L'objectif principal est de tester la durabilité.
C2 adjective /əˈfɪʃəs/

officious

médicule
Meaning
Excessively eager to offer unwanted help or advice; meddlesome.
Example
The officious guard kept interrupting the visitors with unnecessary instructions.
Le garde médicule interrompait les visiteurs avec des instructions inutiles.
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.
A2 verb /ˈɔːfər/

offer

offrir
Meaning
to present something for acceptance or rejection; to propose
Example
She offered to help with the project.
Elle a proposé d’aider avec le projet.
C1 verb /ˌaʊtˈweɪ/

outweigh

avoir plus de poids
Meaning
To be more important, valuable, or significant than something else.
Example
The benefits of the new policy outweigh the risks.
Les avantages de la nouvelle politique l'emportent sur les risques.
C2 noun /oʊd/

ode

ode
Meaning
a lyrical poem, often expressing praise or strong emotions
Example
The poet wrote an ode to the beauty of nature.
Le poète a écrit une ode à la beauté de la nature.
A1 preposition /ɒn/

on

sur
Meaning
physically in contact with and supported by a surface
Example
The book is on the table.
Le livre est sur la table.
B2 noun/verb /ˈoʊvərˌdoʊs/

overdose

overdose
Meaning
An excessive and dangerous amount of a drug; to take too much of a substance.
Example
He was rushed to the hospital after a drug overdose.
Il a été transporté à l'hôpital après une overdose de drogue.
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.
B2 noun /ɔːrˈɡæn.ɪk ˈfɑːr.mɪŋ/

organic farming

agriculture biologique
Meaning
Farming method that avoids synthetic chemicals and fertilizers, using natural methods instead.
Example
Organic farming improves soil health and reduces pollution.
L'agriculture biologique améliore la santé des sols et réduit la pollution.
C2 noun /oʊf/

Oaf

une personne maladroite, stupide ou insensible
Meaning
a clumsy, stupid, or insensitive person
Example
Don't be such an oaf - handle the dishes carefully!
Ne sois pas un oaf - manipule les plats avec soin !
A2 adjective /ˈaʊtdɔːr/

outdoor

en plein air
Meaning
situated, existing, or done outside a building
Example
We planned an outdoor picnic for the weekend.
Nous avons prévu un pique-nique en plein air pour le week-end.
C1 noun /ɒpˈtɒmətri/

optometry

optométrie
Meaning
The practice or profession of examining the eyes and prescribing corrective lenses.
Example
She studied optometry at the university to become an eye specialist.
Elle a étudié l'optométrie à l'université pour devenir spécialiste des yeux.
C1 noun /ˈəʊ.nəs/

onus

responsabilité
Meaning
A duty or responsibility, especially a heavy one.
Example
The onus is on the government to provide relief to the victims.
La responsabilité incombe au gouvernement de fournir de l'aide aux victimes.
B1 verb /əˈkɜːr/

occur

se produire
Meaning
to happen or take place; to be found or present
Example
The accident occurred at the intersection during rush hour.
L'accident est survenu à l'intersection pendant l'heure de pointe.
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.
B2 noun ˈəʊ.və.hed

overhead

frais généraux
Meaning
Ongoing business expenses not directly attributable to creating a product or service.
Example
The company reduced its overhead to increase profits.
L’entreprise a réduit ses frais généraux pour augmenter ses bénéfices.
B2 adjective /əˈpəʊzd/

opposed

opposé
Meaning
being against or in disagreement with something
Example
She is strongly opposed to animal testing.
Elle est fermement opposée aux tests sur les animaux.
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.
A1 interjection /oʊ/

oh

Oh
Meaning
used to express surprise, realization, or understanding
Example
Oh, I didn't know you were here!
Oh, je ne savais pas que tu étais ici !
B1 adjective /ˈaʊtər/

outer

extérieur
Meaning
situated on or toward the outside; external
Example
The outer layer of the jacket is waterproof.
La couche externe de la veste est imperméable.
C1 verb /ˈoʊvərˌhɔːl/

overhaul

révision complète
Meaning
to examine thoroughly and repair or improve something that is worn or ineffective
Example
The company decided to overhaul its outdated computer system.
L'entreprise a décidé de rénover son système informatique obsolète.
A1 adjective /ˈɔːr.ɪndʒ/

Orange

orange
Meaning
having a color between red and yellow like that of a ripe orange fruit
Example
The orange sunset painted the sky magnificently.
Le coucher du soleil orange a peint le ciel magnifiquement.
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.
B1 adverb /ˈʌðərwaɪz/

Otherwise

autrement; sinon
Meaning
in a different way; if not; or else; apart from that
Example
Study hard, otherwise you will fail the exam.
Étudie dur, sinon tu échoueras à l'examen.
B2 noun /əbˈsɛʃən/

obsession

obsession
Meaning
An idea, thought, or concern that continually preoccupies or intrudes on a person's mind.
Example
His obsession with success drove him to work day and night.
Son obsession pour le succès l'a poussé à travailler jour et nuit.
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.
C1 verb /ˌaʊtˈstrɪp/

outstrip

dépasser
Meaning
To go faster or do better than someone or something; to surpass.
Example
The company outstripped its competitors in sales last year.
L'entreprise a dépassé ses concurrents en ventes l'année dernière.
B1 adjective /ˌoʊvərˈsiːz/

overseas

à l'étranger
Meaning
in or to a foreign country across the sea
Example
He went overseas for higher education.
Il est allé à l'étranger pour ses études supérieures.
C1 adjective /ˌaʊtˈspoʊkən/

Outspoken

franc
Meaning
frank; speaking directly
Example
She is known for being outspoken about social issues.
Elle est connue pour être franche sur les problèmes sociaux.
C1 adjective /ˌɒbsəˈliːt/

obsolete

obsolète
Meaning
No longer in use or out of date.
Example
Floppy disks are now completely obsolete.
Les disquettes sont maintenant complètement obsolètes.
A1 pronoun /ˈʌðərz/

others

autres
Meaning
people or things distinct from the ones already mentioned or known
Example
I like to spend time with others.
J'aime passer du temps avec les autres.
A1 pronoun /aʊər/

our

notre
Meaning
belonging to or associated with the speaker and one or more other people
Example
This is our house.
C'est notre maison.
C2 noun /ɒkˈteɪvoʊ/

octavo

octavo (taille de livre obtenue en pliant une feuille en huit parties)
Meaning
A size of book page resulting from folding a sheet of paper into eight leaves (sixteen pages).
Example
The old library contained rare octavo editions of Shakespeare.
La vieille bibliothèque contenait des éditions rares en octavo de Shakespeare.
B2 noun /əbˈzɜːvər/

observer

observateur
Meaning
a person who watches or notices something
Example
The observer took notes during the meeting.
L'observateur a pris des notes pendant la réunion.
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 verb /ˌoʊvərˈiːt/

overeat

bonheur
Meaning
To eat more food than the body needs.
Example
She tends to overeat when she is stressed.
Elle ne pouvait pas cacher son bonheur quand elle a reçu le prix.
B2 noun /ˈaʊtbɜːrst/

outburst

éruption soudaine de colère ou d'émotion
Meaning
a sudden release of strong emotion or activity
Example
She had an angry outburst during the meeting.
Elle a eu un accès de colère pendant la réunion.
C1 noun/verb /ˈoʊvərˌhæŋ/

overhang

saillie
Meaning
To extend outward and hang over something; a projecting part.
Example
The roof overhang provides shade in the summer.
Le surplomb fournit de l'ombre en été.
B2 adjective, verb /əbˈskjʊr/

obscure

obscur
Meaning
Not clearly expressed or understood; to make something difficult to see or understand.
Example
The meaning of the poem was obscure to most readers.
La signification du poème était obscure pour la plupart des lecteurs.
C1 noun /ˈɑːlɪˌɡɑːrki/

oligarchy

oligarchie
Meaning
A small group of people having control of a country, organization, or institution.
Example
The nation was ruled by a wealthy oligarchy that controlled all resources.
La nation était dirigée par une oligarchie riche qui contrôlait toutes les ressources.
B1 noun /ˈɒbstəkəlz/

obstacles

obstacles
Meaning
Things that block one's way or prevent or hinder progress.
Example
Obstacles in life can often lead to valuable lessons.
Les obstacles dans la vie mènent souvent à des leçons précieuses.
B2 noun /ˈɑp.tə.mɪst/

Optimist

optimiste
Meaning
a person who tends to be hopeful and confident about the future; someone who sees the good side of things
Example
As an optimist, she always believed things would improve.
En tant qu'optimiste, elle a toujours cru que les choses s'amélioreraient.
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.
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.
A1 adjective /oʊˈkeɪ/

ok

d'accord
Meaning
used to indicate agreement, approval, or understanding
Example
Okay, let's go to the park.
D'accord, allons au parc.
C1 noun /ˈɔr.ə.tər/

Orator

orateur
Meaning
a public speaker, especially one who is eloquent or skilled in speaking
Example
The famous orator delivered an inspiring speech.
Le célèbre orateur a prononcé un discours inspirant.
C1 noun ɔːrˈdiːl

ordeal

épreuve difficile
Meaning
A physical or mental painful experience that must be endured
Example
Surviving the wilderness was a tough ordeal for them.
Survivre dans la nature a été une épreuve difficile pour eux.
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.
C2 adjective /əbˈstrɛpərəs/

obstreperous

tapageur et difficile à contrôler
Meaning
Noisy and difficult to control.
Example
The obstreperous students disrupted the class.
Les étudiants tapageurs ont perturbé le cours.
C1 verb ˈɔː.kɪ.streɪ.tɪd

orchestrated

orchestré
Meaning
Planned or coordinated carefully and deliberately.
Example
The attacks were orchestrated with precision.
Les attaques ont été orchestrées avec précision.
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 /ˈɒbsɪkwiːz/

obsequies

rites funéraires
Meaning
Funeral rites or ceremonies.
Example
The obsequies for the late leader drew thousands of mourners.
Les rites funéraires du leader défunt ont attiré des milliers de personnes en deuil.
B1 verb /ˈɒpəreɪt/

operate

fonctionner
Meaning
to function; to control or manage; to perform surgery
Example
The surgeon will operate on the patient tomorrow.
Le chirurgien opérera le patient demain.
C2 noun /ˌoʊpəˈlɛsəns/

opalescence

opalescence
Meaning
a milky or pearly appearance of a surface like that of an opal
Example
The pearl had a gentle opalescence under the light.
La perle avait une douce opalescence sous la lumière.
C1 adjective /ˌoʊvərˈrɔt/

overwrought

agité / excessivement nerveux
Meaning
extremely agitated or nervous; excessively elaborate
Example
She was too overwrought to speak clearly after the accident.
Elle était trop agité pour parler clairement après l'accident.
B1 noun ˈɒk.sɪ.dʒən

oxygen

oxygène. Un gaz incolore et inodore, essentiel pour la vie.
Meaning
A colorless, odorless reactive gas, the chemical element of atomic number 8 and the life-supporting component of the air.
Example
Oxygen is vital for life.
L'oxygène est vital pour la vie.
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/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.
B2 noun /ˈɒt.ər/

Otter

loutre
Meaning
a mammal with webbed feet that lives near water and feeds on fish
Example
The playful otter swam gracefully in the river.
La loutre joueuse nageait gracieusement dans la rivière.
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.
C1 verb ˈɔːr.kɪ.streɪt

orchestrate

orchestrer
Meaning
To plan or coordinate the elements of (a situation) to produce a desired effect, especially surreptitiously.
Example
He skillfully orchestrated the entire event.
Il a habilement orchestré l'ensemble de l'événement.
C2 verb /əbˈtruːd/

obtrude

intruser
Meaning
to force oneself or one's ideas into a situation uninvited or inappropriately
Example
He didn’t want to obtrude into their private conversation.
Il ne voulait pas intruser dans leur conversation privée.
C2 noun /ˌɑːpərˈtuːnɪzəm/

opportunism

opportunisme
Meaning
The practice of taking advantage of opportunities regardless of principles or ethics.
Example
His decision was driven by opportunism, not values.
Sa décision a été motivée par l'opportunisme, pas par des valeurs.
B2 verb /ˌoʊvərˈteɪk/

overtake

doubler
Meaning
to catch up with and pass someone or something; to surpass
Example
The runner managed to overtake his competitor in the final lap.
Le coureur a réussi à doubler son concurrent lors du dernier tour.
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.
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 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.