impregnable
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C2 adjective /ɪmˈprɛɡnəbl̩/

impregnable

impenetrable
Meaning
Unable to be captured, broken into, or defeated.
Example
The fortress was considered impregnable by the enemy.
La fortaleza fue considerada impenetrable por el enemigo.
A1 preposition /ˈɪntuː/

into

adentro
Meaning
expressing movement or direction to the inside of something
Example
She walked into the room quietly.
Ella entró silenciosamente en la habitación.
C2 verb /ɪˈnjʊər/

inure

acostumbrar
Meaning
To become accustomed to something, especially something unpleasant.
Example
Soldiers quickly became inured to the harsh conditions.
Los soldados rápidamente se acostumbraron a las duras condiciones.
C1 noun /ˌɪməˈrælɪti/

immorality

inmoralidad
Meaning
the quality of being immoral; behavior that violates accepted moral standards
Example
The community condemned the immorality of the corrupt officials.
La comunidad condenó la inmoralidad de los funcionarios corruptos.
C2 noun /ɪnˈtɛnʃən/

intension

contenido interno
Meaning
The internal content of a concept; the set of attributes implied by a word or phrase.
Example
The intension of the word 'dog' includes being a mammal and domesticated.
La intensión de la palabra 'perro' incluye ser un mamífero y ser domesticado.
C1 adjective /ˌɪnədˈmɪsəbl̩/

inadmissible

inadmisible
Meaning
Not allowed, especially as evidence in a court of law.
Example
The judge ruled the evidence inadmissible.
El juez dictaminó que la evidencia era inadmisible.
C2 verb /ɪnˈveɪ/

inveigh

criticar duramente
Meaning
To speak or write about something with great hostility and criticism.
Example
He inveighed against the corruption in government.
Él criticó duramente la corrupción en el gobierno.
C2 adjective /ɪmˌpɜːrˈsweɪdəbl/

impersuadable

inconvencible
Meaning
not able to be convinced or persuaded
Example
She remained impersuadable despite all our arguments.
Ella permaneció inconvencible a pesar de todos nuestros argumentos.
A1 preposition/adverb/adjective/noun /ˌɪnˈsaɪd/

inside

felicidad
Meaning
Situated within something; the inner part of something.
Example
She waited inside the house until the rain stopped.
Ella no pudo ocultar su felicidad cuando recibió el premio.
C2 noun /ˌɪmprɪˈmɑːtər/

imprimatur

imprimátur
Meaning
An official license or approval, especially to publish a book.
Example
The book was released with the official imprimatur of the church.
El libro fue lanzado con el imprimátur oficial de la iglesia.
C1 noun /ˈɪnstɪˌɡeɪtər/

instigator

instigador
Meaning
A person who brings about or initiates something, usually something bad.
Example
The police identified him as the instigator of the violence.
La policía lo identificó como el instigador de la violencia.
A2 preposition /ɪnˈkluːdɪŋ/

including

incluido
Meaning
used to show that someone or something is part of a larger group
Example
Many people attended the event, including students and teachers.
Muchas personas asistieron al evento, incluidos estudiantes y maestros.
B2 verb /ɪnˈfɛkt/

infect

infectar
Meaning
To contaminate with a disease-causing organism.
Example
The virus can infect healthy people quickly.
El virus puede infectar a las personas saludables rápidamente.
C2 noun /ɪˈluːmɪnənt/

illuminant

iluminante
Meaning
A substance or device that produces light.
Example
The lamp acted as an illuminant in the dark cave.
La lámpara actuó como un iluminante en la cueva oscura.
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 /ˌɪndɪˈskraɪbəbəl/

Indescribable

indescriptible
Meaning
impossible to describe or express in words; beyond description
Example
The beauty of the sunset was indescribable.
La belleza del atardecer era indescriptible.
C2 adjective /aɪˈsɒ.krə.nəs/

isochronous

aconteciendo a intervalos de tiempo iguales
Meaning
Occurring at equal time intervals; in unison or synchrony.
Example
The pendulum swings are isochronous, repeating at equal intervals.
Los oscilaciones del péndulo son isócronos, repitiendo a intervalos iguales.
C2 noun /ˈɪmɪˌteɪtər/

imitator

imitador
Meaning
a person who copies the behavior, style, or actions of others
Example
He became famous as an imitator of popular singers.
Se hizo famoso como imitador de cantantes populares.
C1 adjective /ɪnˈvɑːlənˌtɛri/

involuntary

involuntario
Meaning
done without will or conscious control
Example
He gave an involuntary shiver when he heard the loud noise.
Él dio un escalofrío involuntario cuando escuchó el ruido fuerte.
C1 adjective ɪˈluː.sər.i

illusory

ilusorio
Meaning
Based on illusion; not real although seeming to be.
Example
His sense of security was entirely illusory.
Su sensación de seguridad era completamente ilusoria.
C2 adjective /ɪnˈsɪpiənt/

incipient

incipiente
Meaning
in an initial stage; beginning to develop
Example
The incipient storm made the sky turn dark and heavy.
La tormenta incipiente hizo que el cielo se volviera oscuro y pesado.
C2 adjective /ɪnˈsɛndiˌɛri/

incendiary

incendiario / provocador
Meaning
designed to cause fires or stir up conflict
Example
The politician’s incendiary remarks angered the crowd.
Las declaraciones incendiarias del político enfurecieron a la multitud.
C2 noun /ɪnˈtɒksɪkənt/

intoxicant

intoxicante
Meaning
a substance, especially alcohol or a drug, that causes intoxication
Example
Alcohol is the most commonly used intoxicant in many cultures.
El alcohol es el intoxicante más comúnmente usado en muchas culturas.
B2 noun /ɪsˈlɑːm/

islam

islám religión
Meaning
the religion founded by the Prophet Muhammad, based on belief in one God (Allah)
Example
Islam emphasizes peace, justice, and compassion.
El Islam enfatiza la paz, la justicia y la compasión.
C1 noun ɪnˈsɒl.vən.si

insolvency

insolvencia
Meaning
The state of being unable to pay debts owed; bankruptcy.
Example
The company declared insolvency after years of losses.
La empresa declaró la insolvencia después de años de pérdidas.
C2 adjective /ɪnˈkɑːdʒɪtənt/

incogitant

desconsiderado
Meaning
Lacking thought; inconsiderate or thoughtless.
Example
It was incogitant of him to make such a rude comment.
Fue incogitante de su parte hacer un comentario tan grosero.
C2 noun /ɪnˈvɛktɪv/

invective

lenguaje insultante
Meaning
Insulting, abusive, or highly critical language.
Example
The politician’s speech was filled with invective against his opponents.
El discurso del político estaba lleno de invectivas contra sus oponentes.
A2 noun/verb /ˈaɪən/ or /ˈaɪərn/

iron

hierro / plancha
Meaning
a strong, hard metal used in construction; also to press clothes with heat
Example
He used an iron to smooth his shirt.
Él usó una plancha para alisar su camisa.
B2 adjective /ˌɪnəˈproʊpriət/

inappropriate

inapropiado
Meaning
not suitable or proper in the circumstances
Example
It was inappropriate to talk loudly in the library.
Era inapropiado hablar en voz alta en la biblioteca.
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.
C2 adjective /ˈɪnˌbrɛd/

inbred

innato
Meaning
existing naturally in a person or animal; also related to reproduction within a limited community
Example
He has an inbred sense of loyalty.
Él tiene un sentido innato de lealtad.
C2 adjective /ɪnˈvaɪələt/

inviolate

inviolado
Meaning
free from violation, injury, or desecration; kept safe and untouched
Example
The ancient temple remained inviolate for centuries.
El antiguo templo permaneció inviolado durante siglos.
B1 noun /ˈɪnpʊt/

input

entrada, información proporcionada
Meaning
information, advice, or data that is put into a system, device, or process
Example
The manager asked for everyone's input on the new project.
El gerente pidió la opinión de todos sobre el nuevo proyecto.
B2 adjective /ˌɪd.iˈɒt.ɪk/

Idiotic

idiota
Meaning
extremely stupid; foolish; senseless
Example
His idiotic behavior embarrassed everyone at the meeting.
Su comportamiento idiota avergonzó a todos en la reunión.
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.
C2 verb /ɪnˈtɜːr/

inter

enterrar
Meaning
To bury a dead body in the ground.
Example
They decided to inter the soldier with full honors.
Ellos decidieron enterrar al soldado con todos los honores.
B2 verb /ˌɪntərˈviːn/

intervene

intervenir
Meaning
To come between people, groups, or events, often to prevent conflict or improve a situation.
Example
The teacher had to intervene to stop the fight between the students.
La maestra tuvo que intervenir para detener la pelea entre los estudiantes.
C2 adjective /ˌɪnɔːˈspɪʃəs/

Inauspicious

desafortunado
Meaning
unlucky; showing signs that future success is unlikely; unfavorable
Example
The dark clouds seemed inauspicious for the wedding.
Las nubes oscuras parecían desfavorables para la boda.
C1 noun /ˈɪntərˌpleɪ/

interplay

interacción
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.
La interacción entre la cultura y la tecnología moldea la vida moderna.
C2 noun /ˌɪdiəˈsɪŋkrəsi/

idiosyncrasy

idiosincrasia
Meaning
A distinctive or peculiar characteristic, habit, or mannerism unique to an individual.
Example
One of her idiosyncrasies was humming while working.
Una de sus idiosincrasias era tararear mientras trabajaba.
C2 noun /ˈɪn.fɪ.del/

Infidel

infiel
Meaning
a person who does not believe in religion or whose religious beliefs differ from one's own
Example
In historical contexts, crusaders often referred to their enemies as infidels.
En contextos históricos, los cruzados a menudo se referían a sus enemigos como infieles.
C2 verb /ˌɪnkəˈpæsɪteɪt/

incapacitate

incapacitar
Meaning
to deprive someone or something of the ability or strength to function
Example
The severe injury incapacitated the player for the rest of the season.
La grave lesión incapacitó al jugador para el resto de la temporada.
C2 noun /ˈaɪdɪl/

idyll

escena idílica
Meaning
An extremely happy, peaceful, or picturesque episode or scene, often idealized.
Example
Their honeymoon was an idyll on a tropical island.
Su luna de miel fue una escena idílica en una isla tropical.
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.
C2 adjective /ɪnˈɛksərəbl/

inexorable

inexorable
Meaning
Impossible to stop or prevent; relentless.
Example
The inexorable rise of technology is changing every aspect of life.
El inexorable aumento de la tecnología está cambiando cada aspecto de la vida.
B2 verb ˈɪmplɪmentɪd

implemented

implementado
Meaning
Put a decision or plan into effect; carried out or executed.
Example
The master plans were partially implemented.
Los planes maestros fueron implementados parcialmente.
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.
C2 adjective /ɪmˈpɛn.ɪ.tənt/

impenitent

impenitente
Meaning
Not feeling regret or shame about one's actions.
Example
The criminal remained impenitent after the trial.
El criminal permaneció impenitente después del juicio.
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.
B2 noun ɪˈmjuː.nɪ.ti

immunity

inmunidad
Meaning
The ability of an organism to resist a particular infection or toxin by the action of specific antibodies.
Example
A strong immunity protects against infections.
Una fuerte inmunidad protege contra infecciones.
B1 verb /aɪˈdentɪfaɪ/

identify

identificar
Meaning
to recognize; to establish who someone is
Example
Can you identify the suspect?
¿Puedes identificar al sospechoso?
C2 noun /ˌɪkθiˈɒlədʒɪst/

ichthyologist

icthyólogo
Meaning
A scientist who studies fish.
Example
The ichthyologist discovered a new species of fish in the river.
El icthyólogo descubrió una nueva especie de pez en el río.
B1 verb /ˈɪndʒər/

injure

lesionar
Meaning
to cause physical harm or damage to someone or something
Example
He injured his leg while playing football.
Él lesionó su pierna mientras jugaba al fútbol.
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.
C2 noun /ˌɪn.trəˈɡreʃ.ən/

introgression

introducción genética
Meaning
The transfer of genetic information from one species to another through repeated backcrossing.
Example
Introgression plays a significant role in plant breeding.
La introgressión juega un papel importante en la mejora de plantas.
C1 adjective /ˌɪnkənˈkluːsɪv/

inconclusive

inconcluso
Meaning
Not leading to a definite result or decision.
Example
The investigation remained inconclusive due to a lack of evidence.
La investigación permaneció inconclusa debido a la falta de evidencia.
B2 noun /ˌɪntəˈrʌpʃən/

interruption

interrupción
Meaning
the act of stopping or breaking the continuity of something; a pause caused by an external action
Example
The meeting was delayed due to an unexpected interruption.
La reunión se retrasó por una interrupción inesperada.
C2 noun /ˌɪndɛnˈteɪʃən/

indentation

sangría
Meaning
A space left at the beginning of a line of text; a notch or deep recess on a surface.
Example
The teacher asked the students to use proper indentation in their essays.
El profesor pidió a los estudiantes que usaran una sangría adecuada en sus ensayos.
C1 noun /ˌɪnˈdɪsəplɪn/

indiscipline

indisciplina
Meaning
lack of discipline or self-control; failure to obey rules or maintain order
Example
Indiscipline among the students disrupted the learning environment.
La indisciplina entre los estudiantes interrumpió el ambiente de aprendizaje.
A2 adjective /ˈɪntrəstɪd/

interested

interesado
Meaning
Showing curiosity or concern about something.
Example
She is very interested in learning new languages.
Ella está muy interesada en aprender nuevos idiomas.
C2 adjective /ˌɪndaɪˈdʒestəbəl/

Indigestible

indigerible; difícil de digerir
Meaning
difficult or impossible to digest; hard to process in the stomach
Example
The old bread became hard and indigestible.
El pan viejo se volvió duro e indigesto.
C2 noun /ˌɪntərpəˈzɪʃən/

interposition

intervención
Meaning
The act of intervening or coming between two things, often to influence or prevent an outcome.
Example
The manager’s interposition prevented a heated argument from escalating.
La intervención del gerente evitó que una discusión acalorada se intensificara.
C2 adjective /ɪnˈdɛkərəs/

indecorous

indecoroso
Meaning
Not in keeping with good taste and propriety; improper.
Example
His indecorous behavior shocked the audience.
Su comportamiento indecoroso sorprendió a la audiencia.
C2 noun /ˌɪntərˈlɒkjətər/

interlocutor

interlocutor
Meaning
a person who takes part in a conversation or dialogue
Example
She was a skilled interlocutor during the debate.
Ella era una interlocutora hábil durante el debate.
B2 verb /ˈɪr.ɪ.teɪt/

irritate

irritar
Meaning
To make someone annoyed or angry; to cause discomfort or inflammation.
Example
Rubbing your eyes can irritate them.
Frotarse los ojos puede irritarlos.
C1 adjective /ˌɪn.səbˈstæn.ʃəl/

insubstantial

insustancial
Meaning
Lacking strength, substance, or solidity.
Example
The evidence provided was insubstantial and unconvincing.
La evidencia proporcionada fue insustancial y poco convincente.
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.
C2 noun /ˌɪmprɪˈkeɪʃən/

imprecation

maldición
Meaning
A spoken curse or expression of strong condemnation.
Example
The angry crowd hurled imprecations at the corrupt official.
La multitud enojada lanzó maldiciones al funcionario corrupto.
C2 noun /ˌɪn.ɪˈbraɪ.ə.ti/

inebriety

embriaguez
Meaning
the state of being drunk or intoxicated
Example
His frequent inebriety led to the loss of his job.
Su frecuente embriaguez le llevó a perder su trabajo.
C1 adjective /ˈɪntrɪkət/

intricate

intrincado
Meaning
very detailed, complex, and difficult to understand
Example
The artist created an intricate pattern on the wall.
El artista creó un patrón intrincado en la pared.
B2 noun /ˈɪnfənt/

infant

bebé
Meaning
A very young child or baby.
Example
The infant was sleeping peacefully in the cradle.
El bebé estaba durmiendo tranquilamente en la cuna.
C2 noun /ɪmp/

imp

pequeño diablillo travieso
Meaning
a small mischievous devil or sprite; a playful troublemaker
Example
The child was acting like a little imp, hiding his toys everywhere.
El niño se comportaba como un pequeño diablillo, escondiendo sus juguetes por todas partes.
C1 noun /ɪnˈvɜːrʒən/

inversion

inversión
Meaning
A reversal of the normal order, position, or relationship.
Example
In poetry, inversion is often used to create emphasis.
En poesía, la inversión se usa a menudo para crear énfasis.
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.
B2 adjective /aɪˈdentɪkəl/

Identical

idéntico; exactamente igual
Meaning
exactly the same; not different in any way
Example
The twins look completely identical to each other.
Los gemelos se ven completamente idénticos entre sí.
C1 noun /ˈɪŋ.krə.mənt/

Increment

aumento
Meaning
an increase or addition, especially one of a series on a fixed scale; a regular increase in salary
Example
He received an annual increment of five percent in his salary this year.
Recibió un aumento anual del cinco por ciento en su salario este año.
C1 noun /ɪnˈdem.nə.ti/

Indemnity

indemnización
Meaning
security or protection against a loss or other financial burden; compensation for damage or loss
Example
The insurance company provided full indemnity for the damages caused by the flood.
La compañía de seguros proporcionó indemnización completa por los daños causados por la inundación.
C2 adjective /ɪmˈpælpəbəl/

impalpable

intangible
Meaning
unable to be felt by touch; difficult to grasp or understand
Example
There was an impalpable sense of fear in the room.
Había una sensación intangible de miedo en la habitación.
B2 verb /ˈɪl.ə.streɪt/

illustrate

ilustrar
Meaning
to explain or make something clear by using examples, pictures, or comparisons
Example
The teacher used diagrams to illustrate the concept.
El maestro utilizó diagramas para ilustrar el concepto.
C2 noun /ɪmˌpɜːrtərbəˈbɪləti/

imperturbability

imperturbabilidad
Meaning
The quality of being calm and not easily disturbed or upset.
Example
Her imperturbability during the crisis impressed everyone.
Su imperturbabilidad durante la crisis impresionó a todos.
C2 noun /ɪnˈdɛntʃər/

indenture

contrato de servidumbre
Meaning
A formal legal agreement, contract, or document, often relating to work or service.
Example
In the 18th century, many workers came under indenture to work overseas.
En el siglo XVIII, muchos trabajadores estuvieron bajo un contrato de servidumbre para trabajar en el extranjero.
C2 verb /ɪnˈɡreɪʃiˌeɪt/

ingratiate

ganarse el favor de
Meaning
To gain favor or approval by deliberate effort, often in a flattering way.
Example
She tried to ingratiate herself with her boss by complimenting him often.
Ella intentó ingraciarse con su jefe al elogiarlo con frecuencia.
C1 adjective /ɪnˈtɛlɪdʒəbl/

intelligible

Meaning
Able to be understood; clear enough to be comprehended.
Example
Her speech was barely intelligible over the noise.
B2 verb /ɪnˈspekt/

inspect

inspeccionar
Meaning
to examine something carefully to check for problems or faults
Example
The engineer will inspect the building for structural damage.
El ingeniero inspeccionará el edificio por daños estructurales.
C1 noun ˌɪn.toʊˈneɪ.ʃən

intonation

entonación
Meaning
The rise and fall of tone in speech and pronunciation.
Example
Proper intonation enhances the clarity of a speech.
Una buena entonación mejora la claridad de un discurso.
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.
C2 noun /aɪˈoʊtə/

iota

un mínimo
Meaning
An extremely small amount.
Example
He did not show an iota of fear.
No mostró ni un mínimo de miedo.
C2 adjective /ɪˈmɒdɪst/

immodest

presuntuoso / indecente
Meaning
lacking humility or decency; excessively proud or improper
Example
His immodest remarks offended the audience.
Sus comentarios presuntuosos ofendieron a la audiencia.
C1 noun ˌɪn.tuˈɪʃ.ən

intuition

intuición
Meaning
The ability to understand something immediately, without the need for conscious reasoning.
Example
Her intuition told her something was wrong.
Su intuición le dijo que algo estaba mal.
C1 adjective /ˌaɪdiəˈlɪstɪk/

Idealistic

idealista
Meaning
pursuing high principles or ideals; unrealistically optimistic
Example
She has an idealistic view of changing the world.
Ella tiene una visión idealista de cambiar el mundo.
B1 adverb /ɪnˈkrɛdɪbli/

incredibly

increíblemente
Meaning
to a great degree; extremely or unbelievably
Example
The view from the top of the mountain was incredibly beautiful.
La vista desde la cima de la montaña era increíblemente hermosa.
C1 noun /ˌɪn.trəˈspek.ʃən/

introspection

introspección
Meaning
The examination or observation of one's own mental and emotional processes; self-reflection.
Example
Through introspection, she gained insight into her emotions.
A través de la introspección, obtuvo una visión profunda de sus emociones.
C1 noun /ɪmˈpɒs.tər/

Impostor

impostor; fraude
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.
El impostor convenció a todos de que era un doctor hasta que se descubrió que sus credenciales eran falsas.
C1 noun /ˈɪnkwest/

inquest

investigación
Meaning
A legal or official inquiry, especially into the cause of a death.
Example
The inquest revealed the cause of the accident.
La investigación reveló la causa del accidente.
C2 adjective /ˌɪndɪˈvɜːrtɪbəl/

indivertible

no desviable
Meaning
Not able to be turned aside or diverted.
Example
The judge's indivertible attention was on the case.
La atención del juez no podía desviarse del caso.
C1 adjective /ɪmˈpoʊzɪŋ/

imposing

imponente
Meaning
having an appearance that is grand, impressive, or commanding
Example
The castle is an imposing structure overlooking the valley.
El castillo es una estructura imponente que domina el valle.
C1 adjective /ˌɪn.dɪˈspen.sə.bəl/

indispensable

indispensable
Meaning
Absolutely necessary, essential
Example
Water is indispensable for human survival.
El agua es indispensable para la supervivencia humana.
C1 adjective /ˌɪnsɪˈdɛntəl/

incidental

incidental
Meaning
happening as a minor part or in connection with something else
Example
Incidental expenses like snacks and tips were included in the bill.
Gastos incidentales como bocadillos y propinas fueron incluidos en la factura.
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 verb /ˌɪn.trəˈspekt/

introspect

introspectar
Meaning
To examine one's own thoughts, feelings, or mental state.
Example
He often introspects before making important decisions.
Él a menudo se introspecta antes de tomar decisiones importantes.
C2 noun /ˌɪn.ʌnˈdeɪ.ʃən/

inundation

inundación
Meaning
The act of flooding or overwhelming with water or things.
Example
The town suffered from a severe inundation after the heavy rains.
La ciudad sufrió una grave inundación después de las fuertes lluvias.
C2 adjective /ˌɪməˈmɔːriəl/

immemorial

inmemorial
Meaning
Extending back beyond memory or record; ancient.
Example
The tradition has been followed since time immemorial.
La tradición ha sido seguida desde tiempos inmemoriales.
C1 noun /ˈɪmɪnəns/

imminence

inminencia, estado de proximidad
Meaning
the state of being about to happen
Example
The imminence of the storm forced people to take shelter.
La inminencia de la tormenta obligó a la gente a buscar refugio.
B2 verb /ɪnˈdjuːs/

induce

inducir
Meaning
to cause or persuade someone to do something; to bring about a result
Example
The doctor induced sleep with a mild sedative.
El doctor indujo el sueño con un sedante suave.
C2 adjective /ɪnˈvɛtərət/

inveterate

inmutable
Meaning
having a long-established habit, activity, or interest that is unlikely to change
Example
He is an inveterate reader who spends hours in the library every day.
Él es un lector inmutable que pasa horas en la biblioteca todos los días.
C2 adjective /ˌɪnˌɑːpərˈtuːn/

inopportune

momento inoportuno
Meaning
Happening at a bad or inconvenient time.
Example
His call came at the most inopportune moment.
Su llamada llegó en el momento más inoportuno.
C1 noun /ɪnˈsek.tɪ.saɪd/

Insecticide

insecticida
Meaning
a substance used for killing insects; a chemical pesticide that targets insects
Example
The farmer sprayed insecticide on his crops to protect them from harmful bugs.
El agricultor roció insecticida en sus cultivos para protegerlos de los insectos dañinos.
C2 adjective /ˌɪnfəˈlɪsɪtəs/

infelicitous

inadecuado
Meaning
not suitable or well chosen; awkward or unfortunate
Example
His infelicitous remark ruined the atmosphere of the meeting.
Su comentario inadecuado arruinó el ambiente de la reunión.
C2 adjective ɪˈnɛfəbl

ineffable

inefable
Meaning
Too great or extreme to be expressed or described in words.
Example
The beauty of the landscape was ineffable.
La belleza del paisaje era inefable.
C2 noun /ˈɪndələns/

indolence

indolencia
Meaning
Avoidance of activity or exertion; laziness.
Example
His indolence kept him from finishing the project on time.
Su indolencia le impidió terminar el proyecto a tiempo.
C1 adjective /ɪnˈsɪdiəs/

insidious

insidioso
Meaning
Proceeding in a gradual, subtle way but with harmful effects.
Example
The insidious spread of misinformation can damage trust.
La propagación insidiosa de la desinformación puede dañar la confianza.
B2 adjective ˌɪnstrəˈmɛntl

instrumental

instrumental
Meaning
Serving as a crucial means, agent, or tool; having a part in bringing about a result.
Example
Children can be instrumental in building a better society.
Los niños pueden ser instrumentales en la construcción de una sociedad mejor.
C2 verb /ˈɪmprɛɡneɪt/

impregnate

embarazar / impregnar
Meaning
To make pregnant; to fill or saturate with something.
Example
The scientist used a method to impregnate the material with resin.
El científico utilizó un método para impregnar el material con resina.
B2 adjective + noun aɪˈdiːəl ɪnˈvaɪrənmənt

ideal environment

entorno ideal
Meaning
Perfect or most suitable conditions for growth or development
Example
Winter creates an ideal environment for vegetable growth.
El invierno crea un ambiente ideal para el crecimiento de las verduras.
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 /ˌɪnkwɪˈzɪʃən/

inquisition

inquisición
Meaning
A prolonged and intense questioning or investigation, often harsh in nature.
Example
The journalist faced an inquisition from the panel about his sources.
El periodista enfrentó una inquisición del panel sobre sus fuentes.
B1 noun ˌɪnspɪˈreɪʃən

inspiration

inspiración
Meaning
The process of being mentally stimulated to do or feel something, especially to do something creative.
Example
His journey to success became an inspiration for many.
Su viaje al éxito se convirtió en una inspiración para muchos.
C1 noun /ɪnˈsaɪtmənt/

incitement

incitación
Meaning
the action of provoking unlawful or violent behavior
Example
He was arrested for incitement to riot.
Fue arrestado por incitación a la violencia.
B1 adjective /ˈɪnər/

inner

interno
Meaning
Located inside or closer to the center; relating to one’s thoughts or feelings.
Example
She shared her inner thoughts with her best friend.
Ella compartió sus pensamientos internos con su mejor amiga.
B1 verb /ɪnˈvɛs.tɪ.ɡeɪt/

investigate

investigar
Meaning
to carry out a systematic inquiry to discover facts or information
Example
The police will investigate the incident thoroughly.
La policía investigará el incidente a fondo.
C1 adjective /ˌɪlɪˈdʒɪtɪmət/

illegitimate

ilegítimo
Meaning
Not authorized by law, rules, or standards; not recognized as valid.
Example
The court ruled the contract to be illegitimate.
El tribunal dictaminó que el contrato era ilegítimo.