C1 adjective /ˌɪn.dɪˈspen.sə.bəl/

indispensable

Meaning

Absolutely necessary, essential

Example

Water is indispensable for human survival.

L'eau est indispensable à la survie humaine.

C1 adjective /ɪnˈkɒmpɪtənt/

incompetent

incompétent

Meaning

Lacking the necessary ability or skills to do something successfully.

Example

He was fired because he was incompetent at his job.

Il a été licencié parce qu'il était incompétent dans son travail.

C1 adjective /ɪnˈdʌstriəs/

industrious

travailleur

Meaning

Hardworking and diligent in one's duties.

Example

She is an industrious student who always completes her assignments on time.

Elle est une étudiante travailleuse qui termine toujours ses devoirs à temps.

C1 verb /ɪmˈpiːtʃ/

impeach

destituer

Meaning

To charge a public official with misconduct while in office.

Example

The parliament voted to impeach the president.

Le parlement a voté pour destituer le président.

C1 adjective /ˌɪntəˈrɑːɡətɪv/

interrogative

interrogatif

Meaning

Relating to or conveying a question; in grammar, used to form questions.

Example

She raised an interrogative eyebrow when she heard the news.

Elle haussa un sourcil interrogatif lorsqu'elle entendit la nouvelle.

C1 adjective /ɪˈledʒ.ə.bəl/

illegible

illisible

Meaning

Not clear enough to be read; unreadable.

Example

The doctor’s handwriting was almost illegible.

L'écriture du médecin était presque illisible.

C1 noun /ɪnˈsæn.ə.ti/

Insanity

folie; démence

Meaning

the state of being seriously mentally ill; extreme foolishness or irrationality

Example

The defense lawyer argued that his client was not guilty by reason of insanity.

L'avocat de la défense a soutenu que son client n'était pas coupable pour cause de folie.

C1 adjective /ɪnˈsɛp(ə)rəbəl/

inseparable

inséparable

Meaning

Unable to be separated or always together.

Example

The two friends have been inseparable since childhood.

Les deux amis sont inséparables depuis l'enfance.

C1 noun ɪnˌten.sɪ.fɪˈkeɪ.ʃən

intensification

Meaning

The process of becoming or making something more intense or extreme.

Example

The intensification of climate change requires urgent action.

L'intensification du changement climatique nécessite une action urgente.

C1 adjective /ɪnˈstɪŋk.tɪv/

instinctive

instinctif, naturel, automatique

Meaning

Based on instinct; done without conscious thought; natural and automatic.

Example

His instinctive reaction saved his life.

Sa réaction instinctive lui a sauvé la vie.

C1 adjective /ɪnˈæk.tɪv/

Inactive

inactif

Meaning

not active; not working; dormant; idle

Example

The volcano has been inactive for over a century.

Le volcan est inactif depuis plus d'un siecle.

C1 adjective /ɪnˈɔːdəbl/

inaudible

Meaning

Unable to be heard.

Example

Her voice was almost inaudible over the noise.

Sa voix était presque inaudible par-dessus le bruit.

C1 noun /ˌɪnkənˈsɪstənsi/

inconsistency

incohérence

Meaning

The quality of being contradictory, irregular, or not staying the same.

Example

There is an inconsistency between his words and actions.

Il y a une incohérence entre ses paroles et ses actions.

C1 noun /ɪmˈpɛd.ɪ.mənt/

impediment

obstacle

Meaning

A hindrance or obstruction in doing something; something that prevents progress.

Example

Lack of funds is a major impediment to the project.

Le manque de fonds est un obstacle majeur pour le projet.

C1 noun /ˌɪnsəˈfɪʃənsi/

insufficiency

insuffisance

Meaning

The state of not being enough or not being adequate.

Example

The project failed due to the insufficiency of funds.

Le projet a échoué en raison de l'insuffisance des fonds.

C1 adjective /ɪnˈdetɪd/

Indebted

endetté; reconnaissant

Meaning

owing money or gratitude to someone; obligated; grateful

Example

I am deeply indebted to my teacher for all her guidance.

Je suis profondément endetté envers ma professeure pour toute sa guidance.

C1 noun /ɪnˈtruː.ʒən/

intrusion

intrusion non autorisée

Meaning

Unauthorized entry into a system or place without permission

Example

The company detected an intrusion in its server.

L'entreprise a détecté une intrusion dans son serveur.

C1 adjective /ɪˈrɛvərənt/

irreverent

irrévérencieux

Meaning

showing a lack of respect for people or things that are usually respected

Example

The comedian’s irreverent jokes offended some of the audience.

Les blagues irrévérencieuses du comédien ont offensé certains membres du public.

C1 noun /ˌɪn.trəˈvɜːr.ʒən/

introversion

Meaning

The tendency to be inward-looking and shy, preferring solitary activities.

Example

Her introversion made it difficult for her to enjoy large parties.

Son introversion rendait difficile pour elle de profiter des grandes fêtes.

C1 verb /ˈɪrɪˌɡeɪt/

irrigate

arroser

Meaning

to supply water to land or crops; to wash out a wound with water

Example

Farmers irrigate their fields during dry seasons.

Les agriculteurs irriguent leurs champs pendant les saisons sèches.

C1 adjective ˌɪn.təˈstel.ər

interstellar

entre les étoiles, interstellaire, cosmique

Meaning

Occurring or situated between stars.

Example

Scientists study interstellar travel possibilities.

Les scientifiques étudient les possibilités de voyages interstellaires.

C1 adjective /ɪnˈsʌf.ər.ə.bəl/

insufferable

insupportable

Meaning

Too extreme to bear; intolerable.

Example

The heat during the summer was insufferable.

La chaleur pendant l'été était insupportable.

C1 verb /ˈɪmplɪˌkeɪt/

implicate

impliquer

Meaning

To show someone’s involvement in a crime or wrongdoing.

Example

The evidence implicated several officials in the scandal.

Les preuves ont impliqué plusieurs responsables dans le scandale.

C1 adjective /ˌɪndɪˈstrʌktəbl/

indestructible

Meaning

Impossible to destroy or break.

Example

The superhero's shield was said to be indestructible.

On disait que le bouclier du super-héros était indestructible.

C1 noun /ˈɪtʃ.i.nəs/

itchiness

démangeaison

Meaning

The quality or condition of feeling an irritating sensation on the skin that causes a desire to scratch.

Example

Eye itchiness often leads to rubbing.

Les démangeaisons oculaires entraînent souvent des frottements.

C1 noun /ˌɪnkəmˈpliːtnəs/

incompleteness

incomplétude

Meaning

the state of not being complete or whole; lack of necessary parts or fullness

Example

The incompleteness of the report caused delays in the project.

L’incomplétude du rapport a causé des retards dans le projet.

C1 adjective /ɪnˈsɛnsəbl/

insensible

Meaning

Unconscious; unaware of or indifferent to something.

Example

He was insensible to the cold as he lay in the snow.

Il était insensible au froid lorsqu'il était allongé dans la neige.

C1 noun /ɪnˈfɜː.mə.ti/

Infirmity

faiblesse; maladie; fragilité

Meaning

physical or mental weakness; a disease or ailment; frailty

Example

Despite his advanced age and various infirmities, he remained mentally sharp and alert.

Malgré son âge avancé et ses diverses infirmités, il est resté mentalement vif et alerte.

C1 verb /ˈɪnfɪltreɪt/

infiltrate

infiltrer

Meaning

to secretly enter or gain access to a place or group

Example

The spies managed to infiltrate the enemy base.

Les espions ont réussi à infiltrer la base ennemie.

C1 noun /ɪnˈvɜːrʒən/

inversion

Meaning

A reversal of the normal order, position, or relationship.

Example

In poetry, inversion is often used to create emphasis.

Dans la poésie, l'inversion est souvent utilisée pour créer de l'emphase.

C1 adjective /ˌɪn.səˈbɔːr.dɪ.nət/

insubordinate

insubordonné

Meaning

Defiant of authority; disobedient to orders.

Example

The insubordinate employee refused to follow the manager's instructions.

L'employé insubordonné a refusé de suivre les instructions du gestionnaire.

C1 verb /ɪnˈvɪɡ.ər.eɪt/

invigorate

revigorer

Meaning

To give strength or energy to someone or something.

Example

A morning walk can invigorate both body and mind.

Une promenade matinale peut revigorer le corps et l'esprit.

C1 noun /ˌɪnɪkˈspɪəriəns/

inexperience

inexpérience

Meaning

Lack of knowledge or skill in a particular activity or field.

Example

His inexperience in handling negotiations was evident.

Son inexpérience dans la gestion des négociations était évidente.

C1 adjective /ɪnˈɡreɪnd/

ingrained

enraciné

Meaning

Firmly fixed or established; deeply rooted and difficult to change.

Example

His ingrained habits were hard to break.

Ses habitudes enracinées étaient difficiles à briser.

C1 noun /ˌɪnkoʊˈhɪrəns/

incoherence

incohérence

Meaning

The quality of being unclear, confused, or lacking logical connection.

Example

His speech was full of incoherence and difficult to follow.

Son discours était plein d'incohérences et difficile à suivre.

C1 adjective /ɪmˈpɜːrsənl/

impersonal

impersonnel

Meaning

not influenced by, showing, or involving personal feelings; lacking human warmth or emotion

Example

The letter was written in a very impersonal style.

La lettre a été écrite dans un style très impersonnel.

C1 noun /ˌɪnklɪˈneɪʃən/

inclination

Meaning

A natural tendency or urge to act or feel in a particular way.

Example

She has an inclination towards helping others.

Elle a une inclination à aider les autres.

C1 adjective /ɪnˈvɪnsəbl/

invincible

Meaning

too powerful to be defeated or overcome

Example

The team seemed invincible after winning ten matches in a row.

L'équipe semblait invincible après avoir gagné dix matchs d'affilée.

C1 noun /ˌɪntərˈdʒɛkʃən/

interjection

Meaning

a word or phrase used to express sudden emotion or reaction, often standing alone

Example

Words like 'wow' and 'ouch' are common interjections in English.

Des mots comme 'wow' et 'aïe' sont des interjections courantes en anglais.

C1 verb /ɪnˈsaɪt/

incite

inciter

Meaning

to provoke; to stir up

Example

His speech incited the crowd to violence.

Son discours a incité la foule à la violence.

C1 adjective ɪnˈdel.ə.bəl

indelible

indélébile

Meaning

Making marks that cannot be removed; impossible to forget or remove.

Example

Her speech left an indelible mark on the audience.

Son discours a laissé une marque indélébile sur le public.

C1 noun /aɪˈtɪnərɛri/

itinerary

itinéraire

Meaning

A planned route or schedule of a journey or trip.

Example

The travel agent gave us a detailed itinerary for our vacation.

L'agent de voyages nous a donné un itinéraire détaillé pour nos vacances.

C1 noun /ˈɪn.tə.mə.si/

Intimacy

intimité; proximité

Meaning

close familiarity or friendship; closeness; a private cozy atmosphere

Example

The couple valued the emotional intimacy they shared more than material possessions.

Le couple a plus apprécié l'intimité émotionnelle qu'ils partageaient que les biens matériels.

C1 verb ɪˈmɜːrs

immerse

plonger

Meaning

To involve oneself deeply in a particular activity or interest; to surround completely.

Example

Immerse yourself in the new language.

Plongez-vous dans la nouvelle langue.

C1 adjective /ɪnˈkɒŋɡruəs/

incongruous

incongru

Meaning

Not fitting in with or suitable for the surroundings.

Example

His jokes were incongruous during the serious meeting.

Ses blagues étaient incongrues lors de la réunion sérieuse.

C1 adjective /ˈaɪərnˌklæd/

ironclad

inflexible

Meaning

impossible to change, break, or dispute; very strong and firm

Example

The company had an ironclad contract with its suppliers.

L'entreprise avait un contrat inflexible avec ses fournisseurs.

C1 noun ˌɪnfrəˈstrʌktʃərəl dɪˈveləpmənt

infrastructural development

développement infrastructurel

Meaning

The process of building and improving the basic physical and organizational structures and facilities needed for the operation of a society or enterprise.

Example

Infrastructural development is necessary for efficient recycling.

Le développement infrastructurel est nécessaire pour un recyclage efficace.

C1 noun /ˈɪn.tə.lekt/

intellect

Meaning

The ability to think, reason, and understand objectively.

Example

Her intellect is admired by all her colleagues.

Son intellect est admiré par tous ses collègues.

C1 adjective /ˈɪnərmoʊst/

Innermost

le plus profond; le plus personnel

Meaning

most private and secret; deepest; most personal

Example

She shared her innermost feelings with her closest friend.

Elle a partagé ses sentiments les plus profonds avec son ami le plus proche.

C1 noun ˌɪn.tuˈɪʃ.ən

intuition

Meaning

The ability to understand something immediately, without the need for conscious reasoning.

Example

Her intuition told her something was wrong.

Son intuition lui a dit que quelque chose n’allait pas.

C1 noun /ˌɪn.dʒəˈnjuː.ɪ.ti/

ingenuity

ingéniosité

Meaning

The quality of being clever, original, and inventive.

Example

His ingenuity led to groundbreaking innovations.

Son ingéniosité a conduit à des innovations de rupture.

C1 adjective /ˌɪnkəmˈpætəbl/

incompatible

Meaning

Not able to exist or work together without conflict.

Example

Their personalities were completely incompatible.

Leurs personnalités étaient complètement incompatibles.

C1 adjective /ɪnˈhɛrənt/

inherent

inhérent

Meaning

Existing in something as a natural, permanent, or essential quality.

Example

There are inherent risks in extreme sports.

Il existe des risques inhérents dans les sports extrêmes.

C1 noun /ɪnˈɛk.wɪ.ti/

inequity

inégalité

Meaning

Lack of fairness or justice; unequal distribution or treatment.

Example

Social inequity continues to be a global issue.

L'inégalité sociale reste un problème mondial.

C1 noun /ɪˈreləvəns/

irrelevance

irrélevance

Meaning

the quality of not being connected to or important for a particular matter; lack of significance

Example

His long explanation only highlighted the irrelevance of the details to the main issue.

Sa longue explication n’a fait que souligner l’irrélevance des détails pour le sujet principal.

C1 noun /ˌɪnkəmˌpætəˈbɪlɪti/

incompatibility

incompatibilité

Meaning

the state of being unable to exist or work together harmoniously; lack of compatibility

Example

The project failed because of incompatibility between the two software systems.

Le projet a échoué à cause de l’incompatibilité entre les deux systèmes logiciels.

C1 noun /ˌɪmɔːrˈtæləti/

immortality

immortalité

Meaning

the state of living forever; eternal life or lasting fame beyond death

Example

Many ancient cultures believed that heroes could achieve immortality through great deeds.

De nombreuses cultures anciennes pensaient que les héros pouvaient atteindre l’immortalité par de grands exploits.

C1 verb /ɪnˈtɒksɪkeɪt/

intoxicate

bonheur

Meaning

to make someone lose control of their faculties or behavior due to alcohol or drugs

Example

The strong drink quickly intoxicated him.

Elle n'a pas pu cacher son bonheur lorsqu'elle a reçu le prix.

C1 noun /ɪnˈdʒʌŋkʃən/

injunction

injonction

Meaning

A judicial order restraining a person from an action or compelling a certain act.

Example

The court issued an injunction to stop the company from polluting the river.

Le tribunal a émis une injonction pour empêcher l'entreprise de polluer la rivière.

C1 adjective /ˌɪrɪˈspɛktɪv/

Irrespective

indifférent; sans tenir compte

Meaning

without taking something into account; regardless of

Example

All students will be treated equally, irrespective of their background.

Tous les étudiants seront traités de manière égale, indépendamment de leurs antécédents.

C1 noun /ˈɪmɪnəns/

imminence

imminence, état de proximité

Meaning

the state of being about to happen

Example

The imminence of the storm forced people to take shelter.

L'imminence de la tempête a forcé les gens à chercher un abri.

C1 noun /aɪl/

isle

petite île

Meaning

A small island or peninsula, often poetic or literary.

Example

They spent their honeymoon on a beautiful tropical isle.

Ils ont passé leur lune de miel sur une belle île tropicale.

C1 adjective /ˌɪnədˈvɜːrtənt/

inadvertent

involontaire, non intentionnel

Meaning

Not resulting from or achieved through deliberate planning; unintentional.

Example

Her inadvertent mistake caused a delay in the project.

Son erreur involontaire a causé un retard dans le projet.

C1 adjective ˌɪdiəsɪnˈkrætɪk

idiosyncratic

particulier et individuel

Meaning

Relating to idiosyncrasy; peculiar or individual.

Example

His idiosyncratic behavior set him apart from his colleagues.

Son comportement idiosyncratique le distinguait de ses collègues.

C1 verb /ˌɪnstɪˈtjuːʃənəlaɪz/

institutionalize

institutionnaliser

Meaning

to establish something as a formal institution, custom, or practice

Example

The government seeks to institutionalize environmental protection.

Le gouvernement cherche à institutionnaliser la protection de l'environnement.

C1 noun /ɪmˈpɜː.mə.nəns/

impermanence

Meaning

The state or fact of lasting for only a limited period of time.

Example

The philosophy of Buddhism emphasizes the impermanence of life.

La philosophie bouddhiste met l'accent sur l'impermanence de la vie.

C1 noun /ˈɪntərˌpleɪ/

interplay

interaction

Meaning

The way in which two or more things have an effect on each other.

Example

The interplay between culture and technology shapes modern life.

L'interaction entre la culture et la technologie façonne la vie moderne.

C1 adjective /ˈɪmpətənt/

impotent

Meaning

Lacking power, ability, or strength to take effective action.

Example

The citizens felt impotent against the corrupt system.

Les citoyens se sont sentis impuissants face au système corrompu.

C1 verb /ɪnˈfrɪndʒ/

infringe

enfreindre

Meaning

To actively break the terms of a law, agreement, or right.

Example

Copying this software without permission will infringe copyright laws.

Copier ce logiciel sans permission enfreindra les lois sur le droit d'auteur.

C1 adjective /ɪnˈdʌldʒənt/

indulgent

Meaning

Having a tendency to be overly generous or lenient with someone.

Example

The indulgent mother allowed her child to stay up late.

La mère indulgente a permis à son enfant de rester éveillé tard.

C1 adjective /ɪnˈkrɛdjələs/

incredulous

Meaning

unwilling or unable to believe something

Example

He gave her an incredulous look when she claimed she could fly.

C1 noun /ˌɪn.dɪˈsɪʒ.ən/

Indecision

indécision; hésitation; doute

Meaning

the inability to make decisions quickly; uncertainty about what to do

Example

Her indecision about which job offer to accept caused her to miss both opportunities.

Son indécision sur quelle offre d'emploi accepter l'a conduite à manquer les deux opportunités.

C1 adjective /ɪˈrɛfjʊtəbəl/

Irrefutable

irréfutable

Meaning

impossible to deny or disprove; undeniable

Example

The evidence against him was irrefutable.

Les preuves contre lui étaient irréfutables.

C1 adjective /ˌɪnækˈsɛsəbl/

inaccessible

Meaning

unable to be reached, entered, or understood

Example

The remote village is almost inaccessible during the rainy season.

Le village éloigné est presque inaccessible pendant la saison des pluies.

C1 adjective /ˌɪnɔːrˈɡænɪk/

inorganic

inorganique

Meaning

relating to substances that are not derived from living organisms; lacking organic structure or growth

Example

Inorganic compounds are commonly studied in chemistry labs.

Les composés inorganiques sont courants en chimie.

C1 adjective /ɪnˈdefɪnət/

Indefinite

indéfini

Meaning

not clearly defined; uncertain; vague; unlimited in time

Example

The meeting has been postponed for an indefinite period.

La réunion a été reportée pour une période indéfinie.

C1 noun /ɪmˈpɒs.tər/

Impostor

imposteur; fraudeur

Meaning

a person who pretends to be someone else in order to deceive others; a fraud

Example

The impostor convinced everyone he was a doctor until his fake credentials were discovered.

L'imposteur a convaincu tout le monde qu'il était un médecin jusqu'à ce que ses faux diplômes soient découverts.

C1 verb /ˌɪn.tɚˈtwaɪn/

intertwine

connecter ou lier étroitement; tordre ou combiner étroitement

Meaning

To connect or link closely; to twist together or combine closely.

Example

Their lives became intertwined through years of friendship.

Leurs vies se sont entrelacées au fil des années d'amitié.

C1 adjective /ɪmˈpɜːrtɪnənt/

impertinent

Meaning

rude and showing a lack of respect

Example

It was impertinent of him to question the manager's decision.

C'était impertinent de sa part de remettre en question la décision du manager.

C1 adjective /ˌɪn.ɪˈfɛk.tʃu.əl/

ineffectual

inefficace

Meaning

Not producing any or the desired effect; lacking the ability or qualities to achieve a purpose.

Example

The manager’s ineffectual leadership caused the team to lose motivation.

Le leadership inefficace du manager a causé la perte de motivation de l'équipe.

C1 noun /ˈɪnkwest/

inquest

enquête

Meaning

A legal or official inquiry, especially into the cause of a death.

Example

The inquest revealed the cause of the accident.

L'enquête a révélé la cause de l'accident.

C1 verb ɪˈnɔː.ɡjə.reɪ.tɪd

inaugurated

inauguré

Meaning

Begin or introduce (a system, policy, or period) formally.

Example

The organization was inaugurated officially.

L'organisation a été inaugurée officiellement.

C1 noun ɪnˌɛv.ɪ.təˈbɪl.ɪ.ti

inevitability

inévitabilité

Meaning

The quality of being certain to happen and impossible to avoid or prevent.

Example

The inevitability of change is a part of life.

L'inévitabilité du changement fait partie de la vie.

C1 noun ɪˌræʃ.ənˈæl.ɪ.ti

irrationality

irrationalité, absence de logique, déraison

Meaning

The quality of being illogical or unreasonable; lack of rational thought.

Example

His decision was driven by complete irrationality.

Sa décision a été guidée par une irrationalité totale.

C1 noun /ɪnˌtɪmɪˈdeɪʃən/

intimidation

Meaning

The action of frightening or threatening someone to make them do something.

Example

The workers reported cases of intimidation by the management.

Les travailleurs ont signalé des cas d'intimidation par la direction.

C1 verb /ɪˈmɔːrtəlaɪz/

immortalize

immortaliser

Meaning

to preserve the memory of someone or something forever

Example

The statue was built to immortalize the hero’s sacrifice.

La statue a été construite pour immortaliser le sacrifice du héros.

C1 adjective /ɪmˈpɛndɪŋ/

impending

imminent

Meaning

about to happen soon, usually something unpleasant or threatening

Example

The villagers were worried about the impending flood.

Les villageois étaient inquiets de l'inondation imminente.

C1 adjective ɪnɪɡˈzɔːstɪbəl

inexhaustible

inépuisable

Meaning

Unable to be used up or worn out; limitless.

Example

His inexhaustible energy allowed him to work tirelessly on his projects.

Son énergie inépuisable lui a permis de travailler sans relâche sur ses projets.

C1 adjective /ˌɪnkənˈsiːvəbl̩/

inconceivable

inconcevable

Meaning

Impossible to imagine or believe; beyond comprehension.

Example

It seemed inconceivable that she could finish the marathon after such little training.

Il semblait inconcevable qu'elle puisse finir le marathon après si peu d'entraînement.

C1 verb /ɪnˈdaɪt/

indict

inculper

Meaning

to formally accuse someone of committing a serious crime

Example

The grand jury decided to indict the politician for corruption.

Le grand jury a décidé d'inculper le politicien pour corruption.

C1 adjective /ɪnˈvɑːlənˌtɛri/

involuntary

involontaire

Meaning

done without will or conscious control

Example

He gave an involuntary shiver when he heard the loud noise.

Il a eu un frisson involontaire lorsqu'il a entendu le bruit fort.

C1 verb /ɪnˈsɪnjueɪt/

insinuate

insinuer

Meaning

To suggest or hint something indirectly and often unpleasantly.

Example

He insinuated that she had lied about her qualifications.

Il a insinué qu'elle avait menti sur ses qualifications.

C1 adjective /ɪmˈpoʊzɪŋ/

imposing

imposant

Meaning

having an appearance that is grand, impressive, or commanding

Example

The castle is an imposing structure overlooking the valley.

Le château est une structure imposante qui surplombe la vallée.

C1 noun /ˌɪmpɔːrˈteɪʃən/

importation

Meaning

The act of bringing goods or services into a country from abroad

Example

The importation of luxury goods is strictly regulated.

L'importation de produits de luxe est strictement régulée.

C1 verb /ɪmˈpɪndʒ/

impinge

affecter

Meaning

to have an effect or impact on something; to encroach or infringe

Example

The noise from the construction site impinges on our daily activities.

Le bruit du chantier impacte nos activités quotidiennes.

C1 adjective /ɪmˈpɛn.ɪ.trə.bəl/

impenetrable

impénétrable

Meaning

Impossible to pass through or enter; impossible to understand.

Example

The dense forest was nearly impenetrable.

La forêt dense était presque impénétrable.

C1 noun ˈɪn.fər.əns

inference

inférence

Meaning

A conclusion reached on the basis of evidence and reasoning; logical deduction.

Example

Scientists make inferences based on experimental data.

Les scientifiques font des inférences basées sur des données expérimentales.

C1 adverb /ˌɪnsɪˈdɛntəli/

incidentally

d'ailleurs

Meaning

by the way; used to introduce a remark not directly related to the main subject

Example

Incidentally, did you know that she studied in Paris?

D'ailleurs, savais-tu qu'elle avait étudié à Paris ?

C1 adjective /ˈɪɡ.ni.əs/

igneous

igné

Meaning

Formed through the cooling and solidification of magma or lava.

Example

Granite is an igneous rock commonly used in construction.

Le granit est une roche ignée couramment utilisée dans la construction.

C1 noun /ˈɪntrɪkəsi/

intricacy

complexité

Meaning

the quality of being very detailed or complicated

Example

The intricacy of the design impressed everyone.

La complexité du design a impressionné tout le monde.

C1 noun /ɪnˈkɒmpɪtəns/

incompetence

incompétence

Meaning

Lack of ability, skill, or effectiveness in doing something.

Example

The project failed due to the manager’s incompetence.

Le projet a échoué à cause de l'incompétence du manager.

C1 noun /ˈɪm.pæs/

impasse

Meaning

A situation where no progress is possible.

Example

The negotiations reached an impasse, delaying the agreement.

Les négociations ont atteint un impasse, retardant l'accord.

C1 adjective /ɪnˈseɪʃəbl̩/

insatiable

Meaning

impossible to satisfy; always wanting more

Example

Her insatiable curiosity drove her to read every book in the library.

Sa curiosité insatiable l'a poussée à lire tous les livres de la bibliothèque.

C1 noun /ˌɪntərˈmiːdiˌɛri/

intermediary

intermédiaire

Meaning

A person who acts as a link between people in order to try to bring about an agreement; a mediator.

Example

The diplomat served as an intermediary between the two conflicting nations.

Le diplomate a agi comme intermédiaire entre les deux nations en conflit.

C1 adjective /ɪnˈtændʒəbl/

intangible

Meaning

Unable to be touched or grasped; not having a physical presence.

Example

Trust is an intangible quality in relationships.

La confiance est une qualité intangible dans les relations.

C1 adjective ˌɪn.krəˈmen.təl

incremental

incrémental

Meaning

Relating to or denoting an increase or addition, especially one of a series on a fixed scale; proceeding in small stages.

Example

Incremental changes ensure sustainability.

Les changements incrémentaux assurent la durabilité.

C1 adjective /ˌɪlɪˈdʒɪtɪmət/

illegitimate

illégitime

Meaning

Not authorized by law, rules, or standards; not recognized as valid.

Example

The court ruled the contract to be illegitimate.

Le tribunal a jugé que le contrat était illégitime.

C1 noun /ˌɪməˈtjʊərəti/

immaturity

immaturité

Meaning

the state of not being fully developed emotionally, mentally, or physically; lack of maturity

Example

His immaturity made it difficult for him to handle responsibility.

Son immaturité a rendu la gestion des responsabilités difficile.

C1 adjective /ɪˈrɛvəkəbl/

irrevocable

irrévocable

Meaning

Not able to be revoked, changed, or undone.

Example

She made an irrevocable decision to leave the company.

Elle a pris une décision irrévocable de quitter l'entreprise.

C1 adjective /ˌɪnəˈfɛnsɪv/

inoffensive

inoffensif

Meaning

Not likely to offend or provoke; harmless.

Example

His inoffensive remarks kept the conversation friendly.

Ses remarques inoffensives ont maintenu la conversation amicale.

C1 adjective /ɪˈnuːmərəbəl/

Innumerable

innombrable; incalculable; infini

Meaning

too many to be counted; countless; infinite in number

Example

There are innumerable stars in the night sky that we cannot see with our naked eyes.

Il y a d'innombrables étoiles dans le ciel nocturne que nous ne pouvons pas voir à l'œil nu.

C1 adjective /ɪnˈsteɪbəl/

instable

Meaning

not stable; liable to change, collapse, or fail; lacking firmness or reliability

Example

The instable political situation worried foreign investors.

La situation politique instable a inquiété les investisseurs étrangers.

C1 noun /ˈɪn.fən.tri/

Infantry

infanterie

Meaning

soldiers marching or fighting on foot; foot soldiers collectively

Example

The infantry advanced across the battlefield on foot.

L'infanterie a avancé à travers le champ de bataille à pied.

C1 noun /ɪnˈdɪɡ.nə.ti/

Indignity

indignité; humiliation; déshonneur;

Meaning

treatment or circumstances that cause one to feel shame or loss of dignity; humiliation

Example

She refused to suffer the indignity of being searched without proper cause.

Elle a refusé de subir l'indignité d'être fouillée sans raison valable.

C1 noun /ˈɪn.trə.vɜːrt/

introvert

introverti

Meaning

A person who tends to be shy and prefers spending time alone rather than in groups.

Example

As an introvert, he preferred reading over attending parties.

En tant qu'introverti, il préférait lire plutôt qu'assister à des fêtes.

C1 adjective /ˌɪmprɪˈsaɪs/

imprecise

imprécis

Meaning

Not exact or accurate; vague.

Example

His explanation was too imprecise to be helpful.

Son explication était trop imprécise pour être utile.

C1 noun /ɪnˈdʌstriəsnəs/

industriousness

diligence

Meaning

The quality of being hardworking and diligent.

Example

His industriousness earned him a promotion at work.

Sa diligence lui a valu une promotion au travail.

C1 verb /ɪnˈvoʊk/

invoke

invoquer

Meaning

to call upon a higher power, authority, or principle for help, support, or justification

Example

The lawyer invoked the constitution to defend his client.

L'avocat a invoqué la constitution pour défendre son client.

C1 noun /ɪnˈdjuːsmənt/

inducement

incitation

Meaning

something that persuades or encourages someone to do something

Example

The company offered a bonus as an inducement to employees.

L'entreprise a offert une prime comme incitation aux employés.

C1 adjective /ˈɪmpjəd(ə)nt/

impudent

imprudent, insolent

Meaning

not showing due respect for another person; rude

Example

The impudent child talked back to the teacher.

L'enfant impudent a répondu au professeur.

C1 adjective /ɪmˈpæʃənd/

impassioned

passionné

Meaning

Filled with or showing great emotion.

Example

She gave an impassioned speech about human rights.

Elle a prononcé un discours passionné sur les droits de l'homme.