Oyster
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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.
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 verb /ˈɒsɪfaɪ/

ossify

ossifier
Meaning
to turn into bone or become rigid and inflexible
Example
With age, some tissues tend to ossify.
Avec l'âge, certains tissus ont tendance à s'ossifier.
C1 noun /ˈɑːdəsi/

odyssey

long voyage
Meaning
a long, adventurous journey; a series of experiences
Example
Her career has been an odyssey of challenges and achievements.
Sa carrière a été une odyssée de défis et de réussites.
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.
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Becoming outdated or on the way to becoming obsolete.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 noun /ˈɑd.ɪ.ti/

Oddity

étrangeté
Meaning
something that is strange or unusual; a peculiar trait
Example
His habit of sleeping standing up was considered an oddity.
Son habitude de dormir debout était considérée comme une étrangeté.
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.
C2 adjective /ɒˈstɛnsɪv/

ostensive

ostensible
Meaning
clearly demonstrative or pointing out; explicitly shown
Example
The teacher gave an ostensive example to clarify the concept.
L'enseignant a donné un exemple ostensible pour clarifier le concept.
C2 noun /ˌɒktədʒəˈnɛəriən/

octogenarian

octogénaire
Meaning
A person who is between 80 and 89 years old.
Example
The octogenarian still jogs every morning to stay healthy.
L'octogénaire court encore chaque matin pour rester en bonne santé.
C2 adjective /ˈoʊ.vɔɪd/

ovoid

ovale
Meaning
egg-shaped; resembling an oval or ellipse
Example
The artist painted an ovoid shape in the center of the canvas.
L'artiste a peint une forme ovale au centre de la toile.
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.
C2 adjective /ˈɒfɪʃ/

offish

distant
Meaning
Unfriendly, distant, or reserved in manner.
Example
He seemed offish at the party and avoided most conversations.
Il semblait distant à la fête et évitait la plupart des conversations.
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.
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.
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.
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 verb /əˈfɪʃieɪt/

officiate

officier
Meaning
To perform official duties, especially in a ceremony or as a referee.
Example
The priest will officiate the wedding ceremony.
Le prêtre officiera la cérémonie de mariage.
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.
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 /əbˈtruːsɪv/

obtrusive

intrusif
Meaning
noticeable in an unpleasant or unwelcome way; intrusive
Example
The advertisement was so obtrusive that it ruined the user’s experience.
La publicité était tellement intrusive qu'elle a ruiné l'expérience de l'utilisateur.
B2 noun /ˈɒpəreɪtər/

operator

opérateur
Meaning
a person who operates equipment, a business, or controls something
Example
The machine operator ensured that everything ran smoothly.
L'opérateur de la machine s'est assuré que tout fonctionnait correctement.
B2 noun /ɒpˈtɪʃən/

optician

opticien
Meaning
A person who makes or sells glasses and contact lenses.
Example
The optician adjusted my new glasses to fit better.
L'opticien a ajusté mes nouvelles lunettes pour qu'elles s'ajustent mieux.
C2 noun /ˈaʊtˌrɪɡər/

outrigger

structure de stabilisation
Meaning
a projecting structure on a boat, used for stability, or a boat fitted with such support
Example
The fisherman paddled his outrigger canoe across the lagoon.
Le pêcheur a pagayé sa pirogue avec un outrigger à travers la lagune.
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.
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.
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 /ˌɑb.zɚˈveɪ.ʃən/

Observation

observation
Meaning
the action of watching something carefully; a comment or remark
Example
The scientist made careful observations of the experiment.
Le scientifique a fait des observations minutieuses de l'expérience.
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.
C2 adjective /ˈoʊ.kən/

oaken

fait de chêne
Meaning
made of or resembling oak wood
Example
The villagers gathered around the oaken table in the hall.
Les villageois se sont rassemblés autour de la table en chêne dans la salle.
B2 noun /ˈɒp.tɪ.mɪ.zəm/

optimism

optimisme
Meaning
Hopefulness and confidence about the future or the successful outcome of something.
Example
Her optimism helped her overcome difficult times.
Son optimisme l'a aidée à surmonter des moments difficiles.
C2 noun /ˈɔːrdnəns/

ordnance

fournitures militaires
Meaning
Military supplies including weapons, ammunition, and combat equipment.
Example
The army stored ordnance in a secure facility outside the city.
L'armée a stocké des fournitures militaires dans une installation sécurisée en dehors de la ville.
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 /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.
C2 noun /ɔːˈreɪʃən/

oration

discours
Meaning
A formal speech, especially one given on a ceremonial occasion
Example
The president delivered an inspiring oration.
Le président a prononcé un discours inspirant.
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.
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.
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 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.
C1 adjective /ˌɑːpərˈtuːn/

opportune

moment opportun
Meaning
Happening at a suitable or convenient time.
Example
She arrived at an opportune moment to help.
Elle est arrivée à un moment opportun pour aider.
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.
B2 noun /ˈaʊt.saɪ.dər/

Out-sider

étranger
Meaning
a person who does not belong to a particular group; someone not accepted by a group
Example
As an outsider, he found it difficult to understand their traditions.
En tant qu'outsider, il a trouvé difficile de comprendre leurs traditions.
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 /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 adjective /ɑːlˈfæktəri/

olfactory

olfactif
Meaning
Relating to the sense of smell.
Example
The perfume activated her olfactory nerves immediately.
Le parfum a immédiatement activé ses nerfs olfactifs.
B2 noun /ˈoʊ.dər/

Odour

odeur
Meaning
a distinctive smell, especially an unpleasant one
Example
The odour of fresh bread filled the kitchen.
L'odeur du pain frais remplissait la cuisine.
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.
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.
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.
C1 adjective ˈɒk.sɪ.də.tɪv

oxidative

Relatif à l'oxydation
Meaning
Related to or caused by oxidation, especially cellular damage from free radicals.
Example
Excess stress can lead to oxidative damage in cells.
Le stress excessif peut entraîner des dommages oxydatifs dans les cellules.
C1 verb /ˌaʊtˈduː/

outdo

surpasser
Meaning
To do better than someone else; to surpass.
Example
She always tries to outdo her classmates in exams.
Elle essaie toujours de surpasser ses camarades de classe lors des examens.
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.
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.
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.
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.
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.
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.
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.
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.
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 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.
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 adverb /əˈfɪʃəli/

officially

officiellement
Meaning
in a formal or authorized way
Example
The building was officially opened by the mayor.
Le bâtiment a été officiellement inauguré par le maire.
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.
C1 noun /ˈɒn.slɔːt/

onslaught

assaut
Meaning
A fierce or destructive attack.
Example
The village faced an onslaught of enemy forces.
Le village a fait face à un assaut des forces ennemies.
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.
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.
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.
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.
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 /ˌfæʃ.ənd/

Outdated

obsolète
Meaning
obsolete; no longer current
Example
This computer software is completely outdated.
Ce logiciel informatique est complètement obsolète.
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.
C2 verb /ˌoʊvərˈliːp/

overleap

sauter par-dessus
Meaning
To jump over something; to omit or disregard something.
Example
He managed to overleap the fence easily.
Il a réussi à sauter la clôture facilement.
B2 adjective /aʊtˈreɪdʒəs/

outrageous

scandaleux
Meaning
Shockingly bad or excessive; very unusual or amusing.
Example
The comedian told an outrageous joke.
Le comédien a raconté une blague scandaleuse.
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 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.
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.
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 adjective /ˌoʊvərˈbɛrɪŋ/

overbearing

autoritaire
Meaning
unpleasantly or arrogantly domineering
Example
His overbearing attitude made everyone uncomfortable.
Son attitude autoritaire a mis tout le monde mal à l'aise.
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 adjective /ˈəʊ.dər.əs/

Odorous

parfumé; aromatique
Meaning
having a strong smell; fragrant; aromatic
Example
The garden was filled with odorous flowers.
Le jardin était rempli de fleurs parfumées.
C2 adjective /ˈoʊ.pən ˈhæn.dɪd/

Open-handed

généreux; libéral
Meaning
Generous; liberal; giving freely;
Example
He is very open-handed with his money and always helps those in need.
Il est très généreux avec son argent et aide toujours ceux qui en ont besoin.
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 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 /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 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.
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 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.
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.
C1 noun /oʊˈveɪʃən/

ovation

ovation
Meaning
an enthusiastic show of approval, especially by clapping hands
Example
The actor received a standing ovation after his performance.
L'acteur a reçu une ovation debout après sa performance.
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.
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 noun /ˈoʊvərˌsiːər/

overseer

superviseur
Meaning
a person who supervises work or workers; a manager
Example
The overseer made sure the workers followed safety rules.
Le superviseur s'est assuré que les travailleurs respectaient les règles de sécurité.
B2 noun /ɒdz/

odds

probabilité
Meaning
the likelihood or probability of something happening; chances for or against something
Example
The odds of winning the lottery are very low.
Les chances de gagner à la loterie sont très faibles.
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 /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 /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 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.
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 /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.
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.
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.
A2 verb /oʊˈbeɪ/

obey

obéir
Meaning
to follow orders or instructions; to comply with rules
Example
Children should obey their parents and teachers.
Les enfants doivent obéir à leurs parents et enseignants.
B2 verb /ˌoʊvərˈwɛlm/

overwhelm

accabler
Meaning
to overpower someone emotionally or physically; to be too much to handle
Example
She was overwhelmed with gratitude after receiving the help.
Elle était submergée de gratitude après avoir reçu de l'aide.
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 /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 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.
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.
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.
C2 noun /ˈɔːfəl/

offal

abats
Meaning
the internal organs and entrails of an animal used as food; waste parts
Example
The butcher prepared sausages using pork offal.
Le boucher a préparé des saucisses en utilisant des abats de porc.
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 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 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.
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.
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.
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.
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 adjective /aʊtˈstændɪŋ/

outstanding

exceptionnel
Meaning
extremely good or impressive; not yet resolved or paid
Example
She received an award for her outstanding performance.
Elle a reçu un prix pour sa performance exceptionnelle.
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 !
B2 verb /ɒpt/

opt

choisir
Meaning
to choose or decide to do something instead of something else
Example
Many students opt to study abroad for better opportunities.
De nombreux étudiants choisissent d'étudier à l'étranger pour de meilleures opportunités.
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.