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A1 pronoun, noun, adjective /wʌn/

one

un
Meaning
the number equivalent to the sum of zero and one; a single person or thing
Example
Only one student answered the question.
Un seul étudiant a répondu à la question.
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.
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.
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 verb /ˈɑːbvieɪt/

obviate

éliminer
Meaning
To remove a need or difficulty; to prevent or avoid something.
Example
This new system obviates the need for manual data entry.
Ce nouveau système supprime la nécessité de saisir des données manuellement.
B2 verb /ˌoʊvərˈloʊd/

overload

surcharger
Meaning
to load with too much weight or cargo; to give too much work or information
Example
Don't overload the washing machine or it might break down.
Ne surchargez pas la machine à laver sinon elle pourrait se casser.
C1 noun /ˈɔːrdɪnəns/

ordinance

ordonnance
Meaning
An authoritative rule, law, or decree issued by a city, town, or authority.
Example
The city council passed an ordinance banning smoking in public parks.
Le conseil municipal a adopté une ordonnance interdisant de fumer dans les parcs publics.
C1 adjective /əˈkʌlt/

occult

occultes
Meaning
Relating to mysterious, supernatural, or magical powers and practices.
Example
She had always been fascinated by the occult and its hidden knowledge.
Elle a toujours été fascinée par l'occulte et sa connaissance cachée.
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.
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.
C2 noun (plural) /ˈɔːrdʒiːz/

orgies

orgies
Meaning
Wild gatherings involving excessive indulgence in food, drink, or sexual activity.
Example
The ancient Romans were infamous for their lavish feasts and orgies.
Les anciens Romains étaient infâmes pour leurs festins somptueux et leurs orgies.
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.
B1 noun /ˌɑk.jəˈpeɪ.ʃən/

Occupation

occupation; profession; prise de contrôle
Meaning
a job or profession; the action of taking control of a place
Example
Teaching is her chosen occupation.
L'enseignement est sa profession choisie.
A2 adjective /ɒd/

Odd

étrange; inhabituel; différent de ce qui est normal ou attendu
Meaning
strange; unusual; different from what is normal or expected
Example
That's an odd way to solve the problem.
C'est une façon étrange de résoudre le problème.
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.
A2 noun /ˈɔr.dər/

Order

ordre; séquence
Meaning
a command or instruction; the arrangement of things following a particular sequence
Example
The teacher gave an order to sit down quietly.
L'enseignant a donné un ordre de s'asseoir tranquillement.
A1 noun /ɒkˈtoʊbər/

october

octobre
Meaning
the tenth month of the year in the Gregorian calendar
Example
The weather becomes cooler in October.
Le temps devient plus frais en octobre.
A1 conjunction /ɔːr/

or

ou
Meaning
used to link alternatives
Example
You can have tea or coffee.
Vous pouvez prendre du thé ou du café.
C2 verb ˈɑːb.fə.skeɪt

obfuscate

obscurcir, embrouiller, mystifier
Meaning
Render obscure, unclear, or unintelligible.
Example
Politicians often obfuscate facts to mislead people.
Les politiciens obfusquent souvent les faits pour induire les gens en erreur.
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.
B1 noun /ˌɒp.əˈtjuː.nə.ti/

opportunity

opportunité
Meaning
A favorable chance or set of circumstances that makes it possible to do something.
Example
She seized the opportunity to study abroad.
Elle a saisi l'opportunité d'étudier à l'étranger.
C2 noun /ˈɒlɪv brɑːntʃ/

olive-branch

branche d'olivier
Meaning
A symbol of peace or reconciliation; an offer to end conflict.
Example
He extended an olive-branch to his rival after years of hostility.
Il a tendu une branche d'olivier à son rival après des années d'hostilité.
C1 noun /ˈaʊtˌɡroʊθ/

outgrowth

croissance
Meaning
something that grows out of something else; a natural development or result
Example
The new policy was an outgrowth of years of debate.
La nouvelle politique était une croissance de plusieurs années de débats.
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 /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 /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.
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.
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.
A1 verb, adjective /oʊn/

own

posséder
Meaning
to possess something; belonging to oneself
Example
She owns a beautiful house in the city.
Elle possède une belle maison en ville.
A2 noun əˈlɪm.pɪk ɡeɪmz

Olympic Games

jeux olympiques
Meaning
The world's largest international sports competition held every four years, bringing together athletes from different countries to compete in various sports.
Example
The Olympic Games bring together the world's top athletes.
Les Jeux Olympiques réunissent les meilleurs athlètes du monde.
B2 adjective /ˈɔː.rəl/

Oral

oral; relatif à la bouche
Meaning
spoken rather than written; relating to the mouth
Example
The oral examination will test your speaking skills.
L'examen oral évaluera vos compétences orales.
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 verb /əˈprɛs/

oppress

opprimer
Meaning
to keep someone down by harsh and unfair use of authority; to suppress
Example
The dictator oppressed the people for decades.
Le dictateur a opprimé les gens pendant des décennies.
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.
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.
C1 noun /ˈoʊ.vər spɪl/

Over-spill

débordement
Meaning
the overflow of liquid from a container; excess that cannot be contained
Example
The overspill from the river flooded nearby farms.
Le débordement de la rivière a inondé les fermes voisines.
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.
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.
C1 noun /ˈaʊtˌkraɪ/

outcry

protestation
Meaning
A strong expression of public anger or disapproval.
Example
The decision sparked an outcry among the citizens.
La décision a déclenché une protestation parmi les citoyens.
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.
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.
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.
C2 noun /ˌɑːbdʒərˈɡeɪʃən/

objurgation

réprimande sévère
Meaning
a harsh scolding or strong rebuke
Example
His misconduct earned him a severe objurgation from the manager.
Sa mauvaise conduite lui a valu une réprimande sévère de la part du responsable.
C2 noun /ˌɔːrnɪˈθɑːlədʒi/

ornithology

ornithologie
Meaning
the scientific study of birds
Example
She pursued ornithology to understand the migration patterns of birds.
Elle a poursuivi l'ornithologie pour comprendre les schémas de migration des oiseaux.
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.
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.
C1 verb /uːz/

ooze

suinter
Meaning
to slowly flow or leak out through small openings or pores
Example
Blood began to ooze from the small cut.
Le sang a commencé à suinter de la petite coupure.
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.
C1 noun /əˈfen.dər/

Offender

délinquant; infractionniste de la loi
Meaning
a person who commits an illegal act; someone who breaks the law
Example
The young offender was sentenced to community service.
Le jeune délinquant a été condamné à des travaux d'intérêt général.
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.
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.
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.
C1 noun /ˌəʊvərɪksˌplɔɪˈteɪʃən/

overexploitation

surexploitation
Meaning
The unsustainable use of natural resources at a rate that exceeds their ability to regenerate, leading to depletion and environmental degradation.
Example
Overexploitation of natural resources leads to environmental degradation.
La surexploitation des ressources naturelles conduit à la dégradation de l'environnement.
B1 verb /ˈɒpəreɪtɪŋ/

operating

opérant
Meaning
to control or manage the functioning of something
Example
The company has been operating in this market for five years.
L'entreprise opère sur ce marché depuis cinq ans.
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.
C2 noun /əˈprəʊ.bri.əm/

opprobrium

opprobre, déshonneur
Meaning
Harsh criticism or public disgrace.
Example
The scandal brought opprobrium on the politician.
Le scandale a apporté l'opprobre au politicien.
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.
C2 adjective /ˈoʊ.pən ˈhɑrt.ɪd/

Open-hearted

chaleureux et généreux; sincère et honnête; réceptif chaleureusement;
Meaning
Kind and generous; sincere and honest; warmly receptive;
Example
She welcomed the strangers with an open-hearted smile and invited them for dinner.
Elle a accueilli les étrangers avec un sourire chaleureux et les a invités à dîner.
C1 verb /ˈɒfsɛt/

offset

compenser
Meaning
To counterbalance or compensate for something.
Example
The company's losses were offset by gains in other departments.
Les pertes de l'entreprise ont été compensées par des gains dans d'autres départements.
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.
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.
B2 noun /ˈaʊtˌfɪt/

outfit

tenue
Meaning
A set of clothes worn together, often for a particular occasion.
Example
She wore a beautiful outfit to the party.
Elle portait une belle tenue à la fête.
C1 noun /oʊθ/

Oath

serment
Meaning
a solemn promise or declaration; a sworn statement
Example
The doctor took an oath to help patients.
Le médecin a prêté serment pour aider les patients.
B1 noun /aʊl/

Owl

hibou
Meaning
a nocturnal bird of prey with large eyes and a hooked beak
Example
The owl hooted softly in the darkness of the forest.
Le hibou hululait doucement dans l'obscurité de la forêt.
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.
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.
B1 noun /ˈɑb.stə.kəl/

Obstacle

obstacle
Meaning
something that blocks or makes progress difficult; a barrier
Example
Bad weather was the main obstacle to our journey.
Le mauvais temps était le principal obstacle à notre voyage.
C1 noun /əbˈdʒɛktər/

objector

opposant
Meaning
a person who expresses opposition or disapproval to something
Example
The objector raised his concerns during the town meeting.
L'opposant a exprimé ses préoccupations lors de la réunion municipale.
B2 noun, verb /ˈaʊtlɔː/

outlaw

hors-la-loi, interdire
Meaning
as a noun: a person who breaks the law and lives outside its protection; as a verb: to make something illegal
Example
The government decided to outlaw the harmful practice.
Le gouvernement a décidé d'interdire la pratique nuisible.
B2 noun /ˈɔːrɡənaɪzər/

organizer

organisateur
Meaning
a person who arranges or coordinates activities, events, or groups; a tool or item used to keep things in order
Example
She worked as the main organizer of the international conference.
Elle était l’organisatrice principale de la conférence internationale.
A1 pronoun /aʊərz/

ours

le nôtre
Meaning
belonging to or associated with us
Example
This victory is ours.
Cette victoire est la nôtre.
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 /ˌɒn.əˌmæt.əˈpiː.ə/

onomatopoeia

onomatopée
Meaning
The formation of a word from a sound associated with what is named.
Example
The word 'buzz' is an example of onomatopoeia.
Le mot 'buzz' est un exemple d'onomatopée.
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.
C2 adjective /ˈɒsiəs/

osseous

osseux
Meaning
consisting of or turned into bone; bony
Example
The fossil showed osseous structures of the ancient creature.
Le fossile a montré des structures osseuses de la créature ancienne.
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.
B2 noun /ɔːˈræŋ.ʊˌtæŋ/

Orang-Outang

orang-outang
Meaning
a large arboreal ape with long reddish hair, long arms, and hooked hands and feet, native to Borneo and Sumatra
Example
The orangutan swings gracefully through the forest canopy.
L'orang-outang se balance gracieusement à travers la canopée de la forêt.
C1 noun /ˈoʊvərˌtoʊn/

overtone

connotation subtile
Meaning
A subtle quality, implication, or additional meaning beyond the obvious.
Example
His speech had political overtones that were hard to ignore.
Son discours avait des connotations politiques qu'il était difficile d'ignorer.
C1 noun /ˈɔr.ə.kəl/

Oracle

oracle
Meaning
a person regarded as a source of wise counsel; in ancient times, a priest or priestess acting as a medium
Example
The ancient Greeks consulted the oracle at Delphi.
Les anciens Grecs consultaient l'oracle de Delphes.
B1 adjective /ˌoʊvərˈweɪt/

overweight

surpoids
Meaning
heavier than is considered healthy or normal
Example
The doctor advised him to lose weight as he was overweight.
Le médecin lui a conseillé de perdre du poids car il était en surpoids.
C2 noun /ˌɔːrnɪˈθɒlədʒɪst/

ornithologist

ornithologue
Meaning
a scientist who studies birds
Example
The ornithologist spent years studying migratory birds.
L'ornithologue a passé des années à étudier les oiseaux migrateurs.
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 ˌoʊ.vɚˈɡreɪ.zɪŋ

overgrazing

surpâturage
Meaning
The practice of allowing livestock to graze to the point of damaging vegetation.
Example
Overgrazing leads to soil erosion and loss of biodiversity.
Le surpâturage conduit à l'érosion des sols et à la perte de biodiversité.
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 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 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.
B2 noun/verb /ˈaʊtreɪdʒ/

outrage

indignation
Meaning
A strong feeling of anger and shock; to arouse anger or shock.
Example
The unfair decision caused public outrage.
La décision injuste a provoqué une indignation publique.
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.
C1 adjective /əbˈdʒek.ʃən.ə.bəl/

Objectionable

objectionnable
Meaning
arousing distaste or opposition; unpleasant or offensive
Example
His objectionable behavior made everyone uncomfortable.
Son comportement objectionnable a rendu tout le monde mal à l'aise.
C2 adjective /ˌɒbsəˈlɛsnt/

obsolescent

obsolète
Meaning
Becoming outdated or on the way to becoming obsolete.
Example
The obsolescent technology could not compete with modern devices.
La technologie obsolète ne pouvait pas concurrencer les appareils modernes.
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.
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.
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.
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.
B2 noun /ˈoʊ.vər ɡroʊθ/

Over growth

surcroissance
Meaning
excessive growth beyond normal size; too much development or expansion
Example
The overgrowth of weeds made the garden look untidy.
La surcroissance des mauvaises herbes a rendu le jardin désordonné.
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.
C1 noun /ˈoʊ.mən/

Omen

un signe de bonne ou mauvaise chance future
Meaning
an event regarded as a sign of future good or bad luck
Example
Many people consider a black cat crossing your path a bad omen.
Beaucoup de gens considèrent qu'un chat noir traversant votre chemin est un mauvais présage.
B1 verb /oʊ/

owe

devoir
Meaning
to be under obligation to pay or repay; to be indebted
Example
I owe my success to my parents' support.
Je dois mon succès au soutien de mes parents.
C1 verb /aʊst/

oust

évincer
Meaning
To remove someone from a position or place of power or authority.
Example
The rebels ousted the dictator from power.
Les rebelles ont évincé le dictateur du pouvoir.
C1 noun /əbˈstrʌkʃən/

obstruction

obstacle
Meaning
Something that blocks or gets in the way; the action of obstructing.
Example
There was an obstruction on the railway track.
Il y avait un obstacle sur la voie ferrée.
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.
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.
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.
A1 adjective /əʊˈkeɪ/

okay

d'accord
Meaning
used to express agreement or acceptance
Example
It's okay to leave early today.
Il est d'accord de partir tôt aujourd'hui.
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.
B1 verb অকার্স

occurs

se produit
Meaning
Happens or takes place, especially as a result of something.
Example
Snowfall occurs in regions with freezing temperatures.
La neige se produit dans les régions où les températures sont inférieures à zéro.
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.
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.
A1 verb /ˈoʊpən/

open

ouvrir
Meaning
to move something so as to allow access; to begin
Example
Please open the door for me.
s'il vous plaît ouvrez la porte pour moi.
B2 noun oʊˈbiː.sə.t̬i

obesity

obésité
Meaning
The condition of being grossly fat or overweight.
Example
Obesity increases the risk of diabetes and heart disease.
L'obésité augmente le risque de diabète et de maladies cardiaques.
C2 verb /əbˈvɜːrt/

obvert

inverser
Meaning
To turn something so as to face in a different direction; in logic, to convert a proposition by negating both subject and predicate.
Example
The teacher asked the students to obvert the statement for practice.
Le professeur a demandé aux étudiants de convertir la déclaration pour s'exercer.
B1 noun ˌɒpəˈtjuːnɪtiz

opportunities

opportunités
Meaning
A set of circumstances that makes it possible to do something; chances for advancement or success.
Example
Opportunities for jobs decreased.
Les opportunités d'emploi ont diminué.
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.
C2 verb /ˌoʊvərˈstraɪd/

overstride

franchir en faisant de grands pas
Meaning
To stride over something; to step across with long steps.
Example
He managed to overstride the narrow stream with ease.
Il a réussi à franchir le ruisseau étroit avec facilité.
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.
B2 noun /ˌɒb.zəˈveɪ.ʃənz/

observations

observation
Meaning
The action or process of observing something carefully.
Example
Observations of distant galaxies provide new insights.
Les observations des galaxies lointaines offrent de nouvelles perspectives.
C2 adjective /ˈɔːrnəri/

ornery

irritable
Meaning
bad-tempered and combative; stubborn
Example
The ornery old man refused to leave his chair.
Le vieil homme irritable a refusé de quitter sa chaise.
C1 verb /aʊtˈwɪt/

outwit

déjouer
Meaning
to defeat or gain an advantage over someone by being more clever or cunning
Example
The fox managed to outwit the hunters.
Le renard a réussi à duper les chasseurs.
C2 adjective /ˌoʊpəˈlɛsənt/

opalescent

opalescent
Meaning
showing or reflecting a milky, iridescent light like an opal
Example
The opalescent sky glowed with shades of pink and blue.
Le ciel opalescent brillait avec des nuances de rose et de bleu.
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.