oxidation
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C1 noun ˌɒk.sɪˈdeɪ.ʃən

oxidation

oxydation
Meaning
A chemical reaction that involves the combination of a substance with oxygen, often causing deterioration.
Example
Oxidation causes metal surfaces to weaken.
L'oxydation affaiblit les surfaces métalliques.
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.
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.
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 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.
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 + 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.
B2 adverb /ˈoʊpənli/

Openly

ouvertement; publiquement
Meaning
in a frank and honest way; without concealment; publicly
Example
She spoke openly about her struggles with mental health.
Elle a parlé ouvertement de ses luttes avec la santé mentale.
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.
C1 adjective /ɒmˈnɪv.ər.əs/

Omnivorous

omnivore
Meaning
eating both plants and animals; feeding on various kinds of food
Example
Bears are omnivorous animals that eat both plants and meat.
Les ours sont des animaux omnivores qui mangent à la fois des plantes et de la viande.
B1 noun ˌɔː.ɡən.aɪˈzeɪ.ʃənz

organizations

organisations
Meaning
Organized groups of people with a particular purpose
Example
Organizations play a key role in policymaking.
Les organisations jouent un rôle clé dans l'élaboration des politiques.
C1 noun /əbˈzɜːvəns/

observance

observance
Meaning
The practice of following a custom, rule, or religious law.
Example
The festival is held in observance of a centuries-old tradition.
Le festival est organisé en observance d'une tradition séculaire.
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 /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 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.
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 adjective /ˌɑːp.təˈmɪs.tɪk/

optimistic

optimiste
Meaning
hopeful and confident about the future
Example
She is optimistic about the success of her new project.
Elle est optimiste quant au succès de son nouveau projet.
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.
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 adjective ˌɒp.ərˈeɪ.ʃən.əl

operational

opérationnel
Meaning
In working order; ready for use.
Example
The space project will be operational by 2025.
Le projet spatial sera opérationnel d'ici 2025.
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 adjective /əbˈsɛsɪv/

obsessive

obsessionnel
Meaning
Relating to or characterized by an obsession; thinking about something too much.
Example
He has an obsessive interest in cleanliness.
Il a un intérêt obsessionnel pour la propreté.
C2 verb /ˈɑːblɪˌɡeɪt/

obligate

obliger
Meaning
to bind legally or morally; to compel someone to do something
Example
The contract obligates the company to provide timely service.
Le contrat oblige l'entreprise à fournir un service ponctuel.
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 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.
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 /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.
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.
C2 noun /ˌɔːrəˈtɔːri.oʊ/

oratorio

composition musicale religieuse
Meaning
A large-scale musical composition for orchestra, choir, and soloists, usually on a sacred theme, performed without costumes or scenery.
Example
Handel's 'Messiah' is one of the most famous oratorios ever written.
Le 'Messie' de Handel est l'un des oratorios les plus célèbres jamais écrits.
C2 noun /ˈɒbsɪkwi/

obsequy

obsèque
Meaning
A funeral rite, usually used in plural form obsequies.
Example
The village gathered for the obsequy of their beloved teacher.
Le village s'est réuni pour l'obseque de leur cher professeur.
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 /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.
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.
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.
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.
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 adverb /ˈɒdli/

oddly

étrangement
Meaning
in a strange or unusual way; unexpectedly
Example
Oddly, he didn’t seem upset by the bad news.
Étrangement, il ne semblait pas bouleversé par la mauvaise nouvelle.
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.
C2 noun /ˈəʊpəs/

opus

œuvre créative
Meaning
A creative work, especially a large and important piece of music or art.
Example
The composer considered the symphony his greatest opus.
Le compositeur considérait la symphonie comme sa plus grande œuvre créative.
B2 noun /ˈoʊtˌmiːl/

oatmeal

bouillie d'avoine
Meaning
A type of porridge made from ground oats, often eaten for breakfast.
Example
She eats a bowl of oatmeal every morning for breakfast.
Elle mange un bol de bouillie d'avoine chaque matin au petit-déjeuner.
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.
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 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.
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 /ɑːks/

Ox

bœuf
Meaning
a large strong animal used for pulling heavy loads or plowing fields
Example
The farmer used an ox to plow the field.
L'agriculteur a utilisé un bœuf pour labourer le champ.
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 /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.
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.
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.
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.
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 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 adjective /ˈoʊdiəs/

odious

odieux
Meaning
extremely unpleasant or repulsive
Example
The dictator was remembered for his odious crimes.
Le dictateur a été rappelé pour ses crimes odieux.
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.
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 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 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.
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.
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 /ˌoʊvərprəˈdʌkʃən/

overproduction

surproduction
Meaning
The act of producing more of something than is needed or can be consumed.
Example
The economic crisis was caused by the overproduction of goods.
La crise économique a été causée par la surproduction de biens.
B1 adjective /əˈfɪʃəl/

official

officiel
Meaning
relating to or connected with an authority or public office
Example
He is the official spokesperson for the company.
Il est le porte-parole officiel de l'entreprise.
B2 noun /ˈaʊtˌbreɪk/

outbreak

épidémie
Meaning
a sudden start or occurrence of something unpleasant, like disease or violence
Example
There was an outbreak of flu in the city.
Il y a eu une épidémie de grippe dans la ville.
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 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 adjective ɔːrˈɡæn.ɪk

organic

biologique
Meaning
Produced or involving production without the use of chemical fertilizers, pesticides, or other artificial agents.
Example
Organic farming improves soil health and reduces pollution.
L'agriculture biologique améliore la santé du sol et réduit la pollution.
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.
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 noun /ˈɒkjʊlɪst/

oculist

ophtalmologiste
Meaning
An old-fashioned term for an eye doctor or ophthalmologist.
Example
The village oculist was known for treating various eye diseases.
L'oculiste du village était connu pour traiter diverses maladies des yeux.
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.
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.
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.
B1 adjective /əˈbiː.di.ənt/

Obedient

obéissant
Meaning
willing to comply with orders or instructions; submissive
Example
The obedient student always follows the teacher's instructions.
L'élève obéissant suit toujours les instructions du professeur.
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 !
C2 noun ˌɒbfəsˈkeɪʃən

obfuscation

obfuscation, confusion
Meaning
The action of making something obscure, unclear, or unintelligible.
Example
The obfuscation of the data made it difficult to interpret.
L'obfuscation des données a rendu leur interprétation difficile.
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.
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 noun /ˌɔːrdɪˈneɪʃən/

ordination

ordination
Meaning
The ceremony of conferring holy orders or official religious authority.
Example
The church held a special service for the ordination of new priests.
L'église a organisé un service spécial pour l'ordination de nouveaux prêtres.
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.
C2 noun /ˌɒstɛnˈteɪʃən/

ostentation

ostentation
Meaning
excessive display of wealth or knowledge intended to attract admiration or envy
Example
The billionaire’s party was full of ostentation and luxury.
La fête du milliardaire était pleine d'ostentation et de luxe.
B2 verb /əbˈteɪn/

obtain

obtenir
Meaning
to get or acquire something
Example
You need to obtain a visa before traveling abroad.
Vous devez obtenir un visa avant de partir à l'étranger.
C1 noun /ˈɒfʃuːt/

offshoot

dérivé
Meaning
A branch or result that develops from something larger or more important.
Example
The startup was an offshoot of a major tech company.
La startup était un dérivé d'une grande entreprise technologique.
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.
B2 noun /ˈaʊt.laɪn/

Outline

plan; contour; résumé
Meaning
a general description or plan showing the essential features of something; the main points
Example
The teacher provided an outline of the course syllabus.
L'enseignant a fourni un plan du programme du cours.
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.
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 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.
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.
C1 adjective /ˌaʊtˈlændɪʃ/

outlandish

bizarre
Meaning
Looking or sounding bizarre or unfamiliar; strange.
Example
He wore an outlandish costume to the festival.
Il portait un costume bizarre au festival.
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.
A1 adverb /aʊt/

out

dehors
Meaning
moving or appearing away from the inside or center; not at home or present
Example
He stepped out of the room quietly.
Il est sorti de la pièce silencieusement.
C1 verb /ˌoʊvərˈrʌn/

overrun

envahir
Meaning
to spread over or occupy completely; to exceed a limit or time
Example
The garden was overrun with weeds.
Le jardin était envahi par les mauvaises herbes.
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.
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.
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.
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.
B1 adjective /əˈrɪdʒ.ɪ.nəl/

Original

original; fondamental; authentique
Meaning
first; fundamental; primary; authentic
Example
This is the original document, not a copy.
C'est le document original, pas une copie.
C2 adjective /əˈrækjələr/

oracular

oraculaire
Meaning
Resembling an oracle; giving wise, mysterious, or prophetic statements
Example
Her oracular words left the audience deep in thought.
Ses paroles oraculaires ont laissé l'audience profondément pensive.
B2 verb /ˌoʊvərˈlʊk/

overlook

ignorer
Meaning
to fail to notice or consider something; to have a view from above
Example
It's easy to overlook small details when you're in a hurry.
Il est facile de passer à côté des petits détails quand on est pressé.
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.
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.
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.
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.
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.
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 verb /ˌoʊvərˈθroʊ/

overthrow

bonheur
Meaning
To remove a leader or government from power, often by force.
Example
The rebels planned to overthrow the corrupt regime.
Elle ne pouvait pas cacher son bonheur lorsqu'elle a reçu le prix.
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.
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 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 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.
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.
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.
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 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.
C2 adjective /ɒmˈnɪp.ə.tənt/

omnipotent

omnipotent
Meaning
Having unlimited power; able to do anything; all-powerful.
Example
In many religions, God is considered omnipotent.
Dans de nombreuses religions, Dieu est considéré comme omnipotent.
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 /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 /ˈɒs.trɪtʃ/

Ostrich

autruche
Meaning
a large flightless bird native to Africa with long legs and neck
Example
The ostrich is the world's largest bird.
L'autruche est le plus grand oiseau du monde.
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.
C1 noun /ɔːr/

Oar

aviron
Meaning
a long pole with a flat blade used to row a boat
Example
He dipped the oar into the water and pulled the boat forward.
Il plongea l'aviron dans l'eau et tira le bateau en avant.
C1 noun /ˌɒk.sɪ.dʒɪˈneɪ.ʃən/

oxygenation

fourniture ou traitement d'oxygène
Meaning
The process of supplying or treating with oxygen.
Example
Deep breathing exercises improve oxygenation of the body.
Les exercices de respiration profonde améliorent l'oxygénation du corps.
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.