isotope
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C1 noun /ˈaɪsətəʊp/

isotope

isótopo
Meaning
Atoms of the same element with equal number of protons but different numbers of neutrons.
Example
Carbon-14 is a radioactive isotope used in dating fossils.
El carbono-14 es un isótopo radiactivo utilizado en la datación de fósiles.
C1 verb /ˌɪn.tɚˈtwaɪn/

intertwine

conectar o vincular de cerca; torcer o combinar estrechamente
Meaning
To connect or link closely; to twist together or combine closely.
Example
Their lives became intertwined through years of friendship.
Sus vidas se entrelazaron a lo largo de años de amistad.
C1 noun /ˌɪnkənˈsɪstənsi/

inconsistency

inconsistencia
Meaning
The quality of being contradictory, irregular, or not staying the same.
Example
There is an inconsistency between his words and actions.
Hay una inconsistencia entre sus palabras y acciones.
C1 verb /ɪmˈpɛl/

impel

impulsar
Meaning
to drive, force, or urge someone to do something
Example
Her curiosity impelled her to open the mysterious box.
Su curiosidad la impulsó a abrir la caja misteriosa.
C1 noun /aɪˈdiː.ə.lɪ.zəm/

Idealism

Idealismo
Meaning
the pursuit of high principles and noble goals; unrealistic pursuit of perfection
Example
His youthful idealism motivated him to join various social justice movements.
Su idealismo juvenil lo motivó a unirse a varios movimientos de justicia social.
C1 adverb, adjective /ˌɪnkɑːɡˈniːtoʊ/

incognito

incógnito
Meaning
In disguise or with one's identity concealed.
Example
The celebrity traveled incognito to avoid the paparazzi.
La celebridad viajó incognito para evitar a los paparazzi.
C1 noun /ɪnˈkɒmpɪtəns/

incompetence

incompetencia
Meaning
Lack of ability, skill, or effectiveness in doing something.
Example
The project failed due to the manager’s incompetence.
El proyecto fracasó debido a la incompetencia del gerente.
C1 noun /ɪˈnɜː.ʃə/

Inertia

inercia; falta de actividad
Meaning
a tendency to do nothing or remain unchanged; lack of activity or movement
Example
The team's inertia prevented them from adapting to the rapidly changing market conditions.
La inercia del equipo les impidió adaptarse a las condiciones de mercado en rápido cambio.
C1 adjective /ɪmˈpjʊər/

Impure

impuro
Meaning
contaminated; not clean; mixed with foreign substances
Example
The impure water caused health problems in the village.
El agua impura causó problemas de salud en el pueblo.
C1 verb ɪˈmɜːrs

immerse

sumergir
Meaning
To involve oneself deeply in a particular activity or interest; to surround completely.
Example
Immerse yourself in the new language.
Sumérgete en el nuevo idioma.
C1 verb /ɪmˈbɛd/

imbed

incrustar
Meaning
To fix firmly or deeply in a surrounding mass.
Example
The journalist imbedded himself with the troops to report firsthand.
El periodista se incrustó con las tropas para reportar de primera mano.
C1 noun /ɪnˈfɜːməri/

infirmary

hospital
Meaning
A hospital or place where the sick or injured are cared for.
Example
The school had an infirmary for minor injuries.
La escuela tenía un hospital para lesiones menores.
C1 adjective /ɪnˈtɛlɪdʒəbl/

intelligible

Meaning
Able to be understood; clear enough to be comprehended.
Example
Her speech was barely intelligible over the noise.
C1 noun /ˌɪnkəmˈpliːtnəs/

incompleteness

incompletitud
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.
La incompletitud del informe causó retrasos en el proyecto.
C1 adjective /ɪnˈfriːkwənt/

infrequent

poco frecuente
Meaning
Happening rarely or not often.
Example
He made infrequent visits to his hometown after moving abroad.
Él hacía visitas poco frecuentes a su ciudad natal después de mudarse al extranjero.
C1 adjective /ˌɪndɪˈskriːt/

indiscreet

imprudente
Meaning
Not careful in what one says or does, likely to reveal secrets or offend.
Example
It was indiscreet of him to mention the plan in public.
Fue imprudente de su parte mencionar el plan en público.
C1 adjective /ɪˈledʒ.ə.bəl/

illegible

ilegible
Meaning
Not clear enough to be read; unreadable.
Example
The doctor’s handwriting was almost illegible.
La escritura del doctor era casi ilegible.
C1 verb /ɪnˈsaɪt/

incite

incitar
Meaning
to provoke; to stir up
Example
His speech incited the crowd to violence.
Su discurso incitó a la multitud a la violencia.
C1 adjective /ɪnˈvɜːs/

Inverse

inverso; opuesto
Meaning
opposite in order, nature, or effect; reversed
Example
There is an inverse relationship between price and demand.
Existe una relación inversa entre el precio y la demanda.
C1 adjective /ˌɪndɪˈstɪŋkt/

indistinct

indistinto
Meaning
Not clear or sharply defined; vague or blurred.
Example
The sound of voices was indistinct in the distance.
El sonido de las voces era indistinto a lo lejos.
C1 adjective ˌɪn.təˈstel.ər

interstellar

entre las estrellas, interestelar, cósmico
Meaning
Occurring or situated between stars.
Example
Scientists study interstellar travel possibilities.
Los científicos estudian las posibilidades de viajes interestelares.
C1 noun ˌɪntədɪˈpɛndənsi

interdependency

interdependencia
Meaning
The dependence of two or more people or things on each other.
Example
The interdependency of the countries led to greater cooperation.
La interdependencia de los países llevó a una mayor cooperación.
C1 adjective /ɪnˈkɒŋɡruəs/

incongruous

incongruente
Meaning
Not fitting in with or suitable for the surroundings.
Example
His jokes were incongruous during the serious meeting.
Sus chistes fueron incongruentes durante la reunión seria.
C1 noun ɪnˌten.sɪ.fɪˈkeɪ.ʃən

intensification

intensificación
Meaning
The process of becoming or making something more intense or extreme.
Example
The intensification of climate change requires urgent action.
La intensificación del cambio climático requiere una acción urgente.
C1 verb /ɪmˈpɪndʒ/

impinge

afectar
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.
El ruido de la construcción afecta nuestras actividades diarias.
C1 verb /ˈɪtəreɪt/

iterate

iterar
Meaning
To repeat a process or statement, often to improve or refine.
Example
The software team will iterate the design until it meets user needs.
El equipo de software iterará el diseño hasta que cumpla con las necesidades del usuario.
C1 verb /ˈɪnfɪltreɪt/

infiltrate

infiltrarse
Meaning
to secretly enter or gain access to a place or group
Example
The spies managed to infiltrate the enemy base.
Los espías lograron infiltrarse en la base enemiga.
C1 noun /ˌɪnkjʊˈbeɪʃən/

incubation

el proceso de mantener huevos, células u organismos en las condiciones adecuadas para su desarrollo
Meaning
the process of keeping eggs, cells, or organisms in the right conditions for development
Example
The incubation of the eggs lasted for three weeks.
La incubación de los huevos duró tres semanas.
C1 noun /ˌɪntərˈmɪʃən/

intermission

intermedio
Meaning
A pause or break, especially during a performance or event.
Example
The play had a twenty-minute intermission.
La obra tuvo un intermedio de veinte minutos.
C1 verb /ˈɪmprəvaɪz/

improvise

improvisar
Meaning
To create or perform something spontaneously without preparation.
Example
The actor had to improvise his lines when he forgot the script.
El actor tuvo que improvisar sus líneas cuando olvidó el guion.
C1 adjective /ɪnˈedəbəl/

Inedible

incomible
Meaning
not suitable or safe for eating; not edible
Example
The mushrooms were poisonous and completely inedible.
Los hongos eran venenosos y completamente incomestibles.
C1 adjective /ɪˈnɒkjuəs/

innocuous

inofensivo
Meaning
Not harmful or offensive.
Example
His remark was completely innocuous and not meant to offend anyone.
Su comentario fue completamente inofensivo y no tenía la intención de ofender a nadie.
C1 verb /ɪmˈpiːtʃ/

impeach

impeachar
Meaning
To charge a public official with misconduct while in office.
Example
The parliament voted to impeach the president.
El parlamento votó para impugnar al presidente.
C1 noun ɪmˈpɛə(r)mənt

impairment

daño, discapacidad
Meaning
The state of being damaged or weakened; a disability or handicap.
Example
Hearing impairment can be caused by long-term exposure to loud noise.
La pérdida auditiva puede ser causada por la exposición prolongada a ruidos fuertes.
C1 adjective /ɪnˈɔːdəbl/

inaudible

ininteligible
Meaning
Unable to be heard.
Example
Her voice was almost inaudible over the noise.
Su voz era casi ininteligible sobre el ruido.
C1 adjective /ɪnˈsɒlvənt/

insolvent

insolvente
Meaning
unable to pay debts owed
Example
The insolvent firm could not meet its financial obligations.
La empresa insolvente no pudo cumplir con sus obligaciones financieras.
C1 verb /ɪˈmɔːrtəlaɪz/

immortalize

inmortalizar
Meaning
to preserve the memory of someone or something forever
Example
The statue was built to immortalize the hero’s sacrifice.
La estatua fue construida para inmortalizar el sacrificio del héroe.
C1 adjective /ˌɪnkəmˈpætəbl/

incompatible

incompatible
Meaning
Not able to exist or work together without conflict.
Example
Their personalities were completely incompatible.
Sus personalidades eran completamente incompatibles.
C1 noun /ˈɪn.trə.vɜːrt/

introvert

introvertido
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.
Como introvertido, prefería leer en lugar de asistir a fiestas.
C1 adjective ɪnˈdel.ə.bəl

indelible

indeleble
Meaning
Making marks that cannot be removed; impossible to forget or remove.
Example
Her speech left an indelible mark on the audience.
Su discurso dejó una marca indeleble en la audiencia.
C1 verb /ɪnˈkɜːr/

incur

incurrir
Meaning
To bring upon oneself something undesirable, usually as a result of actions.
Example
He incurred a fine for parking in the wrong place.
Él incurrió en una multa por aparcar en el lugar equivocado.
C1 noun ˌɪnfɛsˈteɪʃən

infestation

infestación, gran número de insectos o animales en un lugar
Meaning
The presence of an unusually large number of insects or animals in a place, causing damage or disease.
Example
The infestation of ants in the kitchen led to immediate pest control measures.
La infestación de hormigas en la cocina llevó a medidas inmediatas de control de plagas.
C1 adjective /ɪmˈpɑːrʃəl/

Impartial

imparcial; neutral
Meaning
treating all sides fairly; unbiased; neutral
Example
A good judge must remain impartial throughout the trial.
Un buen juez debe mantenerse imparcial durante todo el juicio.
C1 noun /ɪnˈfjuːʒən/

infusion

infusión
Meaning
the act of introducing something into another; a drink made by steeping leaves or herbs in liquid
Example
She prepared a calming infusion of chamomile tea.
Ella preparó una infusión calmante de té de manzanilla.
C1 adjective /ˌɪnɑːrˈtɪkjʊlət/

inarticulate

inarticulado
Meaning
Unable to express oneself clearly or effectively in speech or writing.
Example
She became inarticulate with emotion during the speech.
Ella se volvió inarticulada con emoción durante el discurso.
C1 noun /ˈɪmɪdʒəri/

imagery

imaginería
Meaning
visually descriptive or figurative language, especially in a literary work
Example
The poet's use of imagery brought the scene to life.
El uso de imaginería por el poeta dio vida a la escena.
C1 noun ˌɪndɪˈspensəbl səˈpɔːrt

indispensable support

apoyo indispensable
Meaning
Essential assistance that cannot be done without; absolutely necessary help.
Example
Volunteers provide indispensable support to communities.
Los voluntarios proporcionan apoyo indispensable a las comunidades.
C1 adjective ɪmˈpɛkəbl

impeccable

impecable
Meaning
In accordance with the highest standards; faultless.
Example
His impeccable taste in fashion was admired by all his peers.
Su impecable gusto en la moda fue admirado por todos sus compañeros.
C1 noun /ˌɪməˈtjʊərəti/

immaturity

inmadurez
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.
Su inmadurez le dificultó manejar la responsabilidad.
C1 adjective /ɪnˈfɜːm/

infirm

débil
Meaning
Weak, especially due to old age or illness.
Example
The infirm old man needed assistance to walk.
El anciano débil necesitaba ayuda para caminar.
C1 noun /ɪmˈpjʊərəti/

impurity

impureza
Meaning
the state of being unclean or contaminated; a substance that makes something impure
Example
The scientist removed every impurity from the water sample.
El científico eliminó toda impureza de la muestra de agua.
C1 verb /ɪnˈsɪnjueɪt/

insinuate

insinuar
Meaning
To suggest or hint something indirectly and often unpleasantly.
Example
He insinuated that she had lied about her qualifications.
Él insinuó que ella había mentido sobre sus calificaciones.
C1 noun /ˌɪnkoʊˈhɪrəns/

incoherence

incoherencia
Meaning
The quality of being unclear, confused, or lacking logical connection.
Example
His speech was full of incoherence and difficult to follow.
Su discurso estaba lleno de incoherencias y era difícil de seguir.
C1 noun /ɪˈreləvəns/

irrelevance

irrelevancia
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.
Su larga explicación solo resaltó la irrelevancia de los detalles para el tema principal.
C1 verb /ɪmˈploʊd/

implode

implosionar
Meaning
To collapse or burst inward violently.
Example
The old building imploded during the demolition.
El viejo edificio implosionó durante la demolición.
C1 noun /ˈɪd.i.əm/

idiom

modismo
Meaning
A group of words whose meaning is different from the meanings of the individual words.
Example
The idiom 'break the ice' means to start a conversation in a friendly way.
El modismo 'romper el hielo' significa comenzar una conversación de manera amistosa.
C1 adjective /ɪnˈæk.tɪv/

Inactive

inactivo
Meaning
not active; not working; dormant; idle
Example
The volcano has been inactive for over a century.
El volcán ha estado inactivo durante más de un siglo.
C1 noun /ˌaɪ.diˈɒl.ə.dʒi/

ideology

ideología
Meaning
A system of ideas and ideals, especially one that forms the basis of economic or political theory and policy.
Example
Democracy is based on the ideology of freedom and equality.
La democracia se basa en la ideología de la libertad y la igualdad.
C1 adjective /ˌɪnədˈvɜːrtənt/

inadvertent

inadvertido, no intencionado
Meaning
Not resulting from or achieved through deliberate planning; unintentional.
Example
Her inadvertent mistake caused a delay in the project.
Su error inadvertido causó un retraso en el proyecto.
C1 noun /aɪˈtɪnərɛri/

itinerary

itinerario
Meaning
A planned route or schedule of a journey or trip.
Example
The travel agent gave us a detailed itinerary for our vacation.
El agente de viajes nos dio un itinerario detallado para nuestras vacaciones.
C1 verb /ɪnˈvoʊk/

invoke

invocar
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.
El abogado invocó la constitución para defender a su cliente.
C1 adjective ˈɪn.lənd

Inland

del interior
Meaning
Situated in the interior of a country; away from the coast.
Example
Inland transport boosts local trade.
El transporte del interior impulsa el comercio local.
C1 adjective /ɪnˈsɪstənt/

insistent

insistente
Meaning
demanding something firmly and refusing to accept no
Example
The child was insistent on getting a new toy.
El niño era insistente en conseguir un nuevo juguete.
C1 verb /ˌɪntərˈsɛpt/

intercept

interceptar
Meaning
to stop, catch, or seize something on its way from one place to another
Example
The police intercepted the stolen car before it crossed the border.
La policía interceptó el coche robado antes de que cruzara la frontera.
C1 noun ˌɪn.ɪˈfɪʃ.ən.si

inefficiency

ineficiencia
Meaning
The state or quality of not achieving maximum productivity; failure to make the best use of time or resources.
Example
Government inefficiency leads to slow project completion.
La ineficiencia del gobierno conduce a una finalización lenta del proyecto.
C1 adjective ˌɪn.krəˈmen.təl

incremental

incremental
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.
Los cambios incrementales aseguran la sostenibilidad.
C1 adjective /ɪˈnɜːrt/

inert

inactivo
Meaning
lacking the ability or strength to move or act; chemically inactive
Example
The patient remained inert on the bed.
El paciente permaneció inactivo en la cama.
C1 noun /ɪnˈtruː.ʒən/

intrusion

intrusión no autorizada
Meaning
Unauthorized entry into a system or place without permission
Example
The company detected an intrusion in its server.
La empresa detectó una intrusión en su servidor.
C1 adjective /ɪmˈpɛtʃ.u.əs/

impetuous

impulsivo
Meaning
Acting or done quickly and without thought or care; impulsive.
Example
His impetuous decision led to unexpected consequences.
Su decisión impulsiva condujo a consecuencias inesperadas.
C1 noun /ɪˌluːmɪˈneɪʃən/

illumination

iluminación
Meaning
the act of lighting something or making something clear
Example
The street was filled with bright illumination from the lamps.
La calle estaba llena de una iluminacion brillante proveniente de las lamparas.
C1 adjective /ˌaɪ.di.əˈlɒdʒ.ɪ.kəl/

ideological

ideológico
Meaning
Relating to or based on a system of ideas or beliefs.
Example
The two parties are divided by deep ideological differences.
Las dos partes están divididas por profundas diferencias ideológicas.
C1 noun /ˌɪntɪˈmeɪʃən/

intimation

insinuación
Meaning
A subtle or indirect hint or suggestion.
Example
She gave no intimation of her plans.
Ella no dio ninguna insinuación sobre sus planes.
C1 adjective /aɪˈdɪlɪk/

idyllic

idílico y hermoso
Meaning
Like an idyll; extremely happy, peaceful, or picturesque.
Example
They enjoyed an idyllic vacation by the sea.
Disfrutaron de unas vacaciones idílicas junto al mar.
C1 adjective /ɪˈlɒdʒ.ɪ.kəl/

Illogical

Ilógico
Meaning
not reasonable or sensible; lacking logic
Example
It would be illogical to go swimming in such cold weather.
Sería ilógico nadar en un clima tan frío.
C1 adjective /ɪnˈɡreɪnd/

ingrained

arraigado
Meaning
Firmly fixed or established; deeply rooted and difficult to change.
Example
His ingrained habits were hard to break.
Sus hábitos arraigados eran difíciles de romper.
C1 adjective /ɪnˈɛlɪdʒəbəl/

Ineligible

inelegible; no apto; no cualificado
Meaning
not qualified or entitled to participate or be chosen; unsuitable
Example
Students with poor grades are ineligible for the scholarship program.
Los estudiantes con calificaciones bajas no son elegibles para el programa de becas.
C1 adjective ˈɪn.tər.ɪm

interim

interino
Meaning
In or for the intervening period; provisional or temporary.
Example
Interim governments manage transitional phases.
Los gobiernos interinos gestionan fases de transición.
C1 adjective ɪnˈtrɪn.zɪk

intrinsic

intrínseco, esencial, natural
Meaning
Belonging naturally; essential. Existing as a natural or basic part of something.
Example
Creativity is an intrinsic quality of a great artist.
La creatividad es una cualidad intrínseca de un gran artista.
C1 noun /ɪnˈfɜːrnoʊ/

inferno

incendio
Meaning
a large, intense fire that is dangerously out of control
Example
The building turned into an inferno within minutes.
El edificio se convirtió en un incendio en minutos.
C1 adverb /ˌɪnsɪˈdɛntəli/

incidentally

por cierto
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?
Por cierto, ¿sabías que estudió en París?
C1 noun /ˈɪrɪtənt/

irritant

sustancia irritante
Meaning
something that causes irritation or discomfort
Example
Dust is a common irritant for people with allergies.
El polvo es un irritante común para las personas con alergias.
C1 verb /ɪnˈtɒksɪkeɪt/

intoxicate

felicidad
Meaning
to make someone lose control of their faculties or behavior due to alcohol or drugs
Example
The strong drink quickly intoxicated him.
No pudo esconder su felicidad cuando recibió el premio.
C1 noun /ˌɪntərˈdʒɛkʃən/

interjection

interjección
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.
Palabras como 'wow' y 'ouch' son interjecciones comunes en inglés.
C1 adjective /ɪˈmeʒərəbəl/

Immeasurable

inconmensurable
Meaning
too large or extensive to measure; boundless
Example
The immeasurable love of a mother knows no bounds.
El amor inconmensurable de una madre no tiene límites.
C1 noun /ɪmˈprɪzənmənt/

imprisonment

encarcelamiento
Meaning
the act of putting someone in prison; the state of being confined as punishment
Example
He faced imprisonment for violating the court order.
Se enfrentó al encarcelamiento por violar la orden judicial.
C1 adjective /ɪˈrɛvərənt/

irreverent

irreverente
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.
Los chistes irreverentes del comediante ofendieron a algunos de la audiencia.
C1 noun /ɪnˌtɪmɪˈdeɪʃən/

intimidation

intimidación
Meaning
The action of frightening or threatening someone to make them do something.
Example
The workers reported cases of intimidation by the management.
Los trabajadores informaron casos de intimidación por parte de la administración.
C1 adjective /ɪnˈdefɪnət/

Indefinite

indefinido
Meaning
not clearly defined; uncertain; vague; unlimited in time
Example
The meeting has been postponed for an indefinite period.
La reunión se ha pospuesto por un período indefinido.
C1 adjective ˌɪdiəsɪnˈkrætɪk

idiosyncratic

peculiar e individual
Meaning
Relating to idiosyncrasy; peculiar or individual.
Example
His idiosyncratic behavior set him apart from his colleagues.
Su comportamiento idiosincrático lo diferenciaba de sus compañeros.
C1 noun ˌɪnsjʊˈleɪʃən

insulation

aislamiento
Meaning
Material used to prevent heat, sound, or electricity from being transmitted from one area to another.
Example
Insulation of food storage areas can prevent pests from entering.
El aislamiento de las áreas de almacenamiento de alimentos puede evitar que entren plagas.
C1 noun/verb /ˈɪnsɛns/

incense

incienso / enfurecer
Meaning
a substance burned for its sweet smell (noun); to make very angry (verb)
Example
The smell of incense filled the temple, but his rude words incensed her.
El olor del incienso llenó el templo, pero sus palabras groseras la enfurecieron.
C1 adjective /ˈɪnərmoʊst/

Innermost

más profundo; más personal
Meaning
most private and secret; deepest; most personal
Example
She shared her innermost feelings with her closest friend.
Ella compartió sus sentimientos más profundos con su amigo más cercano.
C1 noun /ɪnˈsɜːrdʒənt/

insurgent

insurgente
Meaning
A person who rises in revolt against authority or government.
Example
The army arrested several insurgents after the attack.
El ejército arrestó a varios insurgentes después del ataque.
C1 adjective /ɪmˈprɒbəbl/

improbable

improbable
Meaning
Not likely to be true or to happen.
Example
It seems improbable that he will arrive on time.
Parece improbable que llegue a tiempo.
C1 adjective /ˌɪnhɒˈspɪtəbl/

inhospitable

inhóspito
Meaning
Harsh and difficult to live in; unfriendly or unwelcoming to guests.
Example
The desert is an inhospitable environment for most plants.
El desierto es un ambiente inhóspito para la mayoría de las plantas.
C1 adjective /ˌɪnsərˈmaʊntəbl/

insurmountable

insuperable
Meaning
Too great to be overcome.
Example
The explorers faced insurmountable odds in the desert.
Los exploradores enfrentaron obstáculos insuperables en el desierto.
C1 verb /ɪnˈfjuːz/

infuse

infundir
Meaning
to fill or spread through something; to instill a quality, idea, or feeling
Example
The teacher tried to infuse her students with a love for reading.
La profesora trató de infundir a sus estudiantes con un amor por la lectura.
C1 verb /ɪmˈpɜːrsəneɪt/

impersonate

fingir ser alguien
Meaning
to pretend to be another person in order to entertain or deceive
Example
He was arrested for trying to impersonate a police officer.
Fue arrestado por intentar hacerse pasar por un oficial de policía.
C1 adjective /ɪnˈdiːsənt/

indecent

indecente
Meaning
not conforming to accepted standards of behavior or morality; improper or offensive
Example
He was warned for making an indecent remark during the meeting.
Fue advertido por hacer un comentario indecente.
C1 adjective /ˈaɪərnˌklæd/

ironclad

inquebrantable
Meaning
impossible to change, break, or dispute; very strong and firm
Example
The company had an ironclad contract with its suppliers.
La empresa tenía un contrato inquebrantable con sus proveedores.
C1 adjective /ˌɪnɪkˈsplɪkəbl/

inexplicable

inexplicable
Meaning
Impossible to explain or understand.
Example
The sudden disappearance of the file was inexplicable.
La repentina desaparición del archivo fue inexplicable.
C1 adjective /ɪˈnɔːrdənət/

inordinate

excesivo
Meaning
Excessive or unusually large in degree.
Example
She spent an inordinate amount of time on her phone.
Ella pasó un tiempo excesivo en su teléfono.
C1 adjective /ɪnˈvɛntɪv/

inventive

inventivo
Meaning
Having the ability to create or design new things or to think originally.
Example
The inventor was known for his inventive solutions to everyday problems.
El inventor era conocido por sus soluciones inventivas para los problemas cotidianos.
C1 adjective /ˌɪnstənˈteɪniəs/

instantaneous

instantáneo
Meaning
Happening immediately, without any delay.
Example
The change in temperature was almost instantaneous.
El cambio de temperatura fue casi instantáneo.
C1 noun /ɪmˌpɜː.sənˈeɪ.ʃən/

impersonation

suplantación
Meaning
The action of pretending to be another person for the purpose of entertainment or fraud.
Example
Online impersonation is a serious cybercrime.
La suplantación en línea es un crimen cibernético grave.
C1 noun /ˌɪndɪˈdʒɛstʃən/

indigestion

indigestión
Meaning
Discomfort or pain in the stomach associated with difficulty in digesting food.
Example
He avoided spicy food because it often gave him indigestion.
Él evitó la comida picante porque a menudo le provocaba indigestión.
C1 adjective /ˌɪndɪˈspjuːtəbəl/

Indisputable

indiscutible; innegable; cierto
Meaning
impossible to deny or argue against; undeniable; certain
Example
The evidence against him was indisputable.
La evidencia en su contra era indiscutible.
C1 noun /ˈɪm.pæs/

impasse

impasse
Meaning
A situation where no progress is possible.
Example
The negotiations reached an impasse, delaying the agreement.
Las negociaciones llegaron a un impasse, retrasando el acuerdo.
C1 noun/verb /ˈɪmprɪnt/

imprint

huella
Meaning
A mark or impression made by pressure; to establish or fix firmly in someone's mind.
Example
The event left an indelible imprint on the city's history.
El evento dejó una huella indeleble en la historia de la ciudad.
C1 adjective, noun /ˈɪnvəlɪd/ (adjective), /ɪnˈvælɪd/ (noun)

invalid

inválido
Meaning
Not valid; having no force or effect. Also refers to a person too weak or ill to care for themselves.
Example
The court declared the contract invalid.
El tribunal declaró el contrato inválido.
C1 adjective /ɪnˈflæməbəl/

Inflammable

inflamable; combustible
Meaning
easily set on fire; flammable; combustible
Example
The inflammable material caught fire quickly.
El material inflamable se prendió rápidamente.
C1 adjective /ɪnˈsɛnsəbl/

insensible

insensible
Meaning
Unconscious; unaware of or indifferent to something.
Example
He was insensible to the cold as he lay in the snow.
Él estaba insensible al frío mientras yacía en la nieve.
C1 adjective /ɪˈnænɪmət/

inanimate

objeto inanimado
Meaning
not alive, especially not in the manner of animals and humans; lifeless
Example
The museum was full of inanimate objects from ancient times.
El museo estaba lleno de objetos inanimados de tiempos antiguos.
C1 noun /ɪnˌkɑːsəˈreɪʃən/

incarceration

encarcelamiento
Meaning
the state of being imprisoned or confined
Example
The criminal faced years of incarceration for his crimes.
El criminal enfrentó años de encarcelamiento por sus crímenes.
C1 verb /ˈɪnstɪˌɡeɪt/

instigate

incitar
Meaning
To bring about or initiate an action, often something negative.
Example
He was accused of instigating the riot.
Fue acusado de incitar el motín.
C1 adjective /ˌɪrɪˈspɛktɪv/

Irrespective

irrespetuoso; sin tener en cuenta
Meaning
without taking something into account; regardless of
Example
All students will be treated equally, irrespective of their background.
Todos los estudiantes serán tratados por igual, independientemente de su origen.
C1 adjective /ɪnˈflæməˌtɔːri/

inflammatory

felicidad
Meaning
causing inflammation in the body; arousing anger, hostility, or strong emotion
Example
His inflammatory speech triggered protests across the city.
No pudo esconder su felicidad cuando recibió el premio.
C1 noun ˈɪm.pɪ.təs

impetus

impulso
Meaning
The force or motivation that drives something forward; momentum.
Example
The new policy provided an impetus for economic growth.
La nueva política proporcionó un impulso para el crecimiento económico.
C1 adjective /ɪmˈplɔːzəbl/

implausible

implausible
Meaning
Not seeming reasonable or probable; unlikely to be true.
Example
The story she told was so implausible that no one believed her.
La historia que ella contó era tan implausible que nadie le creyó.
C1 adjective /ɪnˈtjuː.ɪ.tɪv/

intuitive

intuitivo
Meaning
Based on instinctive understanding rather than reasoning.
Example
The software has an intuitive design that makes it easy to use.
El software tiene un diseño intuitivo que lo hace fácil de usar.
C1 adjective /ɪmˈpɜːrsənl/

impersonal

impersonal
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 carta fue escrita en un estilo muy impersonal.