obstinate
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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.
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.
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 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.
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.
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.
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.
C2 noun /əbˈsɪdiən/

obsidian

obsidienne (roche volcanique noire et vitreuse)
Meaning
A hard, dark, glasslike volcanic rock formed by rapid solidification of lava.
Example
The knife was made from sharp obsidian.
Le couteau était fabriqué à partir d'obsidienne tranchante.
C1 noun /oʊˈeɪ.sɪs/

Oasis

oasis
Meaning
a fertile spot in a desert where water is found; a pleasant refuge
Example
The travelers found an oasis after days in the desert.
Les voyageurs ont trouvé un oasis après plusieurs jours dans le désert.
A1 adverb /ɔːf/

off

éteint
Meaning
away from a place, position, or time; not functioning
Example
He turned off the light before leaving the room.
Il a éteint la lumière avant de quitter la pièce.
C2 adjective /ˈɔːrəˌtʌnd/

orotund

voix profonde et claire
Meaning
full, rich, and clear in sound; pompous in style
Example
The actor's orotund voice filled the theater.
La voix profonde de l'acteur a rempli le théâtre.
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.
A2 noun /ˈoʊpənɪŋ/

opening

ouverture
Meaning
an act or instance of beginning something
Example
The opening of the new store was a huge success.
L'ouverture du nouveau magasin a été un grand succès.
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.
C1 adjective /ˈɑp.ər.ə.tɪv/

Operative

actif; en vigueur; fonctionnant; opérationnel;
Meaning
Functioning; in effect; working; active;
Example
The new safety protocols became operative immediately after the accident.
Les nouveaux protocoles de sécurité sont devenus opérationnels immédiatement après l'accident.
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.
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.
A2 adverb; noun /ˌaʊtˈdɔːrz/

outdoors

à l’extérieur
Meaning
outside a building; the natural environment outside
Example
We spent the whole afternoon outdoors enjoying the fresh air.
Nous avons passé tout l’après-midi à l’extérieur à profiter de l’air frais.
B2 noun /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.
B1 adverb /ˈʌðərwaɪz/

Otherwise

autrement; sinon
Meaning
in a different way; if not; or else; apart from that
Example
Study hard, otherwise you will fail the exam.
Étudie dur, sinon tu échoueras à l'examen.
B2 noun 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.
C1 adjective /ˌaʊt ən ˈaʊt/

out-and-out

complet
Meaning
complete; absolute; used to emphasize something extreme
Example
The speech was an out-and-out lie.
Le discours était un mensonge complet.
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.
C1 adjective /əˈblaɪdʒɪŋ/

obliging

serviable
Meaning
Willing to help or do favors; accommodating.
Example
The staff at the hotel were very obliging and friendly.
Le personnel de l'hôtel était très serviable et amical.
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.
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 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.
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.
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.
B2 adjective /ˈɒp.tɪ.məl/

optimal

optimal, le plus favorable
Meaning
Best or most favorable; the most effective under particular conditions.
Example
The optimal temperature for plant growth is around 25°C.
La température optimale pour la croissance des plantes est d'environ 25°C.
B2 adjective /ˈaʊtˌɡoʊɪŋ/

outgoing

sociable
Meaning
Friendly and sociable; inclined to mix with others.
Example
He is an outgoing person who loves meeting new people.
C'est une personne sociable qui aime rencontrer de nouvelles personnes.
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.
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.
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 /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.
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.
A1 pronoun /ˈʌðərz/

others

autres
Meaning
people or things distinct from the ones already mentioned or known
Example
I like to spend time with others.
J'aime passer du temps avec les autres.
A1 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.
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.
B2 verb /ˌoʊvərˈkʌm/

overcome

surmonter
Meaning
To succeed in dealing with a problem or difficulty.
Example
You can overcome procrastination with planning.
Vous pouvez surmonter la procrastination en planifiant.
B2 adjective /ˌoʊvərˈwɛlmɪŋ/

overwhelming

accablant
Meaning
Very intense; overpowering.
Example
Large tasks can feel overwhelming.
Les grandes tâches peuvent sembler accablantes.
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 /əbˈtjuːs/

Obtuse

obtus; lent à comprendre; sans intelligence
Meaning
annoyingly insensitive or slow to understand; lacking in intelligence or perception
Example
He was being deliberately obtuse about the instructions.
Il était délibérément obtus à propos des instructions.
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.
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.
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 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 noun /ˈɔːrkɪd/

Orchid

orchidée
Meaning
a diverse family of flowering plants known for their exotic and often fragrant flowers
Example
The white orchid on the windowsill bloomed for months.
L'orchidée blanche sur le rebord de la fenêtre a fleuri pendant des mois.
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.
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.
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.
C1 noun ˌɒp.tɪ.maɪˈzeɪ.ʃən

optimization

optimisation
Meaning
Improving processes to increase performance and efficiency.
Example
SEO optimization helps websites rank higher on search engines.
L'optimisation SEO aide les sites web à se classer plus haut dans les moteurs de recherche.
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.
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 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 /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 /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 /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 /əˈpɪn.jən/

Opinion

opinion
Meaning
a view or judgment formed about something; a belief or assessment based on grounds short of proof
Example
In my opinion, this is the best solution.
À mon avis, c'est la meilleure solution.
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.
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.
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.
C2 noun /ˈɒn.rʌʃ/

onrush

ruée
Meaning
A sudden powerful forward or downward rush or flow.
Example
The onrush of water swept away the bridge.
La ruée d'eau emporta le pont.
C1 verb ˈɔː.kɪ.streɪ.tɪd

orchestrated

orchestré
Meaning
Planned or coordinated carefully and deliberately.
Example
The attacks were orchestrated with precision.
Les attaques ont été orchestrées avec précision.
C1 noun /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.
A1 adverb /wʌns/

Once

une fois seulement; autrefois
Meaning
one time only; at some time in the past; formerly
Example
I have been to Paris once in my life.
Je suis allé à Paris une fois dans ma vie.
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.
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.
C2 noun /ˈoʊɡər/

ogre

ogre
Meaning
A mythical monster, often depicted as large, hideous, and cruel; metaphorically, a cruel or terrifying person.
Example
The villagers feared the ogre who lived in the dark forest.
Les villageois craignaient l'ogre qui vivait dans la forêt sombre.
C2 adjective /ˈɒpjʊlənt/

opulent

opulent
Meaning
Ostentatiously rich, luxurious, or lavish.
Example
They hosted an opulent wedding with gold decorations.
Ils ont organisé un mariage opulent avec des décorations dorées.
C1 noun /ˈaʊtriːtʃ/

outreach

expansion de l'aide
Meaning
The act of providing services or support to people who might not otherwise have access to them.
Example
The charity launched a new outreach program for the homeless.
L'association a lancé un nouveau programme d'expansion de l'aide pour les sans-abri.
A2 noun /ˈɒm.lət/

Omelet

omelette
Meaning
a dish made from beaten eggs cooked in a frying pan and often folded around a filling
Example
She made a cheese omelet for breakfast.
Elle a préparé une omelette au fromage pour le petit déjeuner.
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.
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.
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.
B1 adjective /ˈɔːɡənaɪzd/

organized

organisé
Meaning
Arranged in a systematic way, especially on a large scale.
Example
An organized approach to work increases productivity and reduces stress.
Une approche organisée du travail augmente la productivité et réduit le stress.
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 /ˈaʊtˌsɛt/

outset

début
Meaning
the beginning or start of something
Example
From the outset, the project seemed ambitious but achievable.
Depuis le début, le projet semblait ambitieux mais réalisable.
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.
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.
B2 noun ˈəʊnəʃɪp

ownership

propriété
Meaning
The act, state, or right of possessing something; legal title to something.
Example
Ownership of resources was crucial.
La propriété des ressources était cruciale.
C1 adjective /ˈɔːrθədɑːks/

orthodox

orthodoxe
Meaning
conforming to traditional beliefs or practices
Example
He comes from a very orthodox family.
Il vient d'une famille très orthodoxe.
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.
C1 noun /ˌɑːk.sɪˈmɔːr.ɒn/

oxymoron

oxymore
Meaning
a figure of speech where two contradictory terms are combined
Example
The phrase 'deafening silence' is a classic oxymoron.
L'expression 'silence assourdissant' est un oxymore classique.
C1 noun /oʊˈmɪʃ.ən/

Omission

omission; exclusion
Meaning
the action of excluding or leaving out someone or something; a failure to include
Example
The omission of his name from the list was intentional.
L'omission de son nom de la liste était intentionnelle.
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.
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 /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 /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.
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 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 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 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.
C1 verb /əbˈstrʌkt/

obstruct

obstruer
Meaning
to block or hinder progress; to prevent or impede movement
Example
The fallen tree obstructed the road for several hours.
L'arbre tombé obstruait la route pendant plusieurs heures.
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.
C2 noun /ˈoʊ.vər.let/

Overlet

surmatelas
Meaning
a thin mattress or pad placed over a bed for additional comfort
Example
The overlet makes the bed more comfortable to sleep on.
Le surmatelas rend le lit plus confortable pour dormir.
C2 noun /ˈɑb.lə.kwi/

Obloquy

critique acerbe ou abus verbal; condamnation publique
Meaning
harsh criticism or verbal abuse; strong public condemnation
Example
The politician faced obloquy after the scandal.
Le politicien a fait face à l'obloquie après le scandale.
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.
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.
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.
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.
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.
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.
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 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.
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.
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.
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.
B2 adjective /ˈɒp.ʃən.əl/

Optional

facultatif
Meaning
not compulsory; left to choice
Example
Wearing a tie is optional for this event.
Porter une cravate est facultatif pour cet événement.
C1 verb əˈblɪt.ə.reɪt

obliterate

anéantir
Meaning
To destroy utterly; wipe out completely, to erase or remove something completely.
Example
The storm obliterated entire villages.
La tempête a anéanti des villages entiers.
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 /ɔːrˈθɑːɡrəfi/

orthography

orthographe
Meaning
The conventional spelling system of a language.
Example
English orthography can be confusing for learners.
L'orthographe anglaise peut être déroutante pour les apprenants.
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.
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.
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.
C1 noun ˈoʊʃən əˌsɪdɪfɪˈkeɪʃən

ocean acidification

acidification océanique
Meaning
The ongoing decrease in the pH of the Earth's oceans, caused by the absorption of carbon dioxide from the atmosphere.
Example
Ocean acidification is caused by atmospheric CO2 absorption.
L'acidification océanique est causée par l'absorption du CO2 atmosphérique.
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.
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.
B1 noun /əˈkeɪ.ʒən/

Occasion

occasion; événement spécial
Meaning
a particular time or instance of an event; a special celebration
Example
Their wedding was a joyous occasion.
Leur mariage était une occasion joyeuse.
B1 adverb /əˈkeɪʒənəli/

Occasionally

occasionnellement; de temps en temps;
Meaning
sometimes; from time to time; not regularly
Example
I occasionally visit my grandmother on weekends.
Je rends visite à ma grand-mère occasionnellement le week-end.
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.