ozone depletion
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B2 noun ˈoʊzoʊn dɪˈpliʃən

ozone depletion

diminution de l'ozone
Meaning
The reduction in the amount of ozone in the Earth's stratosphere, leading to increased UV radiation.
Example
Ozone depletion increases UV radiation.
La déplétion de l'ozone augmente les radiations UV.
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.
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 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.
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.
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.
B1 noun /ˈɔr.ə.ʒɪn/

Origin

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

oxygen production

production d'oxygène
Meaning
The process of generating oxygen through photosynthesis or other means.
Example
Plants are vital for oxygen production and the maintenance of life.
Les plantes sont vitales pour la production d'oxygène et le maintien de la vie.
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 /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.
C2 verb /ˈɔːreɪt/

orate

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

overpass

passerelle
Meaning
A bridge that carries one road or railway over another.
Example
The new overpass reduced traffic congestion in the city.
Le nouveau passerelle a réduit la congestion du trafic en ville.
B2 noun /ˌaʊtˈsaɪdə(r)/

outsider

étranger
Meaning
a person who is not accepted as a member of a particular group or community
Example
As a new student, she often felt like an outsider at school.
En tant que nouvelle étudiante, elle se sentait souvent comme une étrangère à l'école.
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.
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.
C2 noun /ˈɔːrɪndʒfɪn ˈleɪbiːoʊ/

Orangefin labeo

labeo à nageoires orange
Meaning
a freshwater fish species native to South Asian rivers, commonly found in Bangladesh and India
Example
The orangefin labeo is an important food fish in Bangladesh.
Le labeo à nageoires orange est un poisson alimentaire important au Bangladesh.
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 verb /aʊtˈlɪv/

outlive

survivre
Meaning
to live longer than someone or something else
Example
She outlived all her siblings.
Elle a vécu plus longtemps que tous ses frères et sœurs.
B2 noun /əbˈdʒek.ʃən/

Objection

objection; désaccord; protestation;
Meaning
an expression of disagreement or disapproval; a reason for disagreeing
Example
The lawyer raised an objection during the trial.
L'avocat a soulevé une objection pendant le procès.
B1 noun /ˈɑp.ʃən/

Option

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

oblige

obliger
Meaning
to compel or require someone to do something; to help or do a favor
Example
I would be happy to oblige you with the information you need.
Je serais heureux de vous obliger avec les informations dont vous avez besoin.
B2 noun /ˈɒfərɪŋ/

offering

offre
Meaning
something that is given, especially as a gift or contribution
Example
The company’s latest offering is an eco-friendly car.
La dernière offre de l'entreprise est une voiture écologique.
C1 noun /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 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.
B1 adverb /əˈrɪdʒɪnəli/

originally

à l'origine
Meaning
in the beginning, at first
Example
Originally, she wanted to be a doctor.
À l'origine, elle voulait être médecin.
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.
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.
C2 noun /ˈɒlɪv bɑːb/

Olive barb

barbe olive
Meaning
A small freshwater fish with olive-colored body and barbels
Example
The olive barb is commonly found in South Asian rivers.
La barbe olive se trouve couramment dans les rivières d’Asie du Sud.
C2 verb /ˈɑːbdʒərˌɡeɪt/

objurgate

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

obsess

obséder
Meaning
To preoccupy or fill the mind of someone continually and to an excessive degree.
Example
She tends to obsess over small details.
Elle a tendance à s'obséder sur de petits détails.
C1 noun /əbˈzɜːrvətɔːri/

observatory

observatoire
Meaning
A building equipped for observing astronomical or meteorological events.
Example
The observatory is open to the public on weekends.
L'observatoire est ouvert au public le week-end.
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 noun /ˈoʊ.kəm/

oakum

fibre de corde usée
Meaning
loose fibers obtained by untwisting old ropes, used for caulking ships
Example
The shipbuilders used oakum to seal the gaps in the wooden planks.
Les charpentiers de marine ont utilisé de l'okum pour sceller les fissures dans les planches en bois.
C1 noun ˌɒb.səˈlɛs.əns

obsolescence

obsolescence
Meaning
The process of becoming obsolete or outdated and no longer used.
Example
The rapid advancement of technology leads to the obsolescence of old devices.
Le progrès rapide de la technologie entraîne l’obsolescence des anciens appareils.
C1 noun /ˈɑn.set/

Onset

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

observe

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

outpost

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

oblivion

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

omnipotence

omnipotence
Meaning
The quality of having unlimited power or authority.
Example
Many religions describe God’s omnipotence as absolute.
De nombreuses religions décrivent l'omnipotence de Dieu comme absolue.
A2 noun /ˈoʊ.nər/

Owner

propriétaire
Meaning
a person who owns something; someone who has legal possession of property
Example
The owner of the restaurant greeted us warmly.
Le propriétaire du restaurant nous a accueillis chaleureusement.
B2 verb /oʊˈmɪt/

omit

omettre
Meaning
to leave out or exclude; to fail to include something
Example
Please don't omit any important details from your report.
Veuillez ne pas omettre les détails importants dans votre rapport.
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.
C2 noun /ˈoʊdiəm/

odium

odium
Meaning
general or widespread hatred or disgust directed toward someone as a result of their actions
Example
The scandal brought public odium on the corrupt minister.
Le scandale a attiré l'odium public sur le ministre corrompu.
C2 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.
B2 noun /ˈɔr.fən.ɪʒ/

Orphanage

orphelinat
Meaning
an institution for the care and education of children who have lost their parents
Example
The charity built a new orphanage for homeless children.
La charité a construit un nouvel orphelinat pour les enfants sans abri.
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 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.
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.
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.
C1 verb /aʊtˈlæst/

outlast

durer plus longtemps que
Meaning
to continue longer than; to endure beyond someone or something else
Example
The old castle has outlasted many generations.
Le vieux château a duré plus longtemps que de nombreuses générations.
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 adjective /oʊˈbiːs/

obese

obèse
Meaning
Extremely overweight; having an excessive amount of body fat.
Example
The doctor advised the obese patient to adopt a healthier lifestyle.
Le médecin a conseillé au patient obèse d'adopter un mode de vie plus sain.
C2 adjective /ˈɒf.biːt/

offbeat

inhabituel
Meaning
Unusual, unconventional, or different from the norm.
Example
She has a very offbeat sense of humor.
Elle a un sens de l'humour très inhabituel.
B2 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.
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.
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.
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.
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 /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.
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 /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.
B1 adjective, adverb /ˈoʊvərɔːl/

overall

dans l'ensemble
Meaning
in general or as a whole
Example
Overall, the project has been successful.
Dans l'ensemble, le projet a été un succès.
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 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.
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 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.
B2 noun /əˈfens/

Offence

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

operation

opération
Meaning
an act or process of functioning or operating
Example
The hospital performed a successful operation.
L'hôpital a effectué une opération réussie.
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.
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.
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.
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.
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 noun /əbˈstɛtrɪks/

obstetrics

obstétrique
Meaning
The branch of medicine dealing with childbirth and care of women giving birth.
Example
She is studying obstetrics to become a specialist in childbirth.
Elle étudie l'obstétrique pour devenir spécialiste de l'accouchement.
C1 verb /ˌoʊvərˈʃædoʊ/

overshadow

éclipser
Meaning
to appear more important or significant than something else, reducing its impact
Example
The scandal overshadowed his achievements.
Le scandale a éclipsé ses réalisations.
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 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.
C1 noun /oʊˈbɪt.ʃu.er.i/

Obituary

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

ordinal

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

Observant

observateur
Meaning
quick to notice things; watchful; attentive
Example
The observant detective noticed every small detail at the crime scene.
Le détective observateur a remarqué chaque petit détail sur la scène du crime.
C1 adjective /ˈɒptɪməm/

optimum

optimal
Meaning
Most conducive to a favorable outcome; best.
Example
To achieve optimum results, we need to improve efficiency.
Pour obtenir des résultats optimaux, nous devons améliorer l'efficacité.
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.
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.
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.
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.
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 /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.
A1 noun/adjective/adverb /ˌaʊtˈsaɪd/

outside

dehors
Meaning
the external part or surface of something; beyond the boundary
Example
Children were playing outside in the yard.
Les enfants jouaient dehors dans le jardin.
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.
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.
C1 noun /ˈɔɪntmənt/

ointment

onguent
Meaning
A smooth, oily substance applied to the skin for healing or soothing.
Example
The doctor prescribed an ointment for the burn on his arm.
Le médecin a prescrit un onguent pour la brûlure sur son bras.
B2 adjective /ˌoʊvərˈwɛlmɪŋ/

overwhelming

accablant
Meaning
Very intense; overpowering.
Example
Large tasks can feel overwhelming.
Les grandes tâches peuvent sembler accablantes.
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.
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.
B2 noun /əˌrɪʒ.əˈnæl.ə.ti/

Originality

originalité
Meaning
the quality of being novel or unusual; the ability to think independently and creatively
Example
The artist's work showed great originality and creativity.
Le travail de l'artiste a montré une grande originalité et créativité.
C1 adjective /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.
B2 verb əbˈzɜːrvd

observed

observer
Meaning
To celebrate or keep a religious or other festival.
Example
The day is observed annually to raise awareness.
Le jour est observé chaque année pour sensibiliser.
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.
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.
B2 noun /ˌɒpəˈzɪʃən/

opposition

opposition
Meaning
the action of opposing or resisting something
Example
The opposition to the new law was strong.
L'opposition à la nouvelle loi était forte.
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.