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 /ɪmˈplɔːr/

implore

implorar
Meaning
To beg someone earnestly or desperately to do something.
Example
She implored him to stay with her.
Ella le imploró que se quedara con ella.
B2 adverb /aɪˈrɒnɪkli/

ironically

irónicamente
Meaning
in a way that is contrary to what is expected or intended
Example
Ironically, the fire station burned down.
Irónicamente, la estación de bomberos se incendió.
C1 adjective /ɪnˈstɪŋk.tɪv/

instinctive

instintivo, natural, automático
Meaning
Based on instinct; done without conscious thought; natural and automatic.
Example
His instinctive reaction saved his life.
Su reacción instintiva le salvó la vida.
C2 adjective /ɪmˈplækəbl/

implacable

implacable
Meaning
unable to be appeased, calmed, or pacified
Example
The soldiers faced an implacable enemy who refused to surrender.
Los soldados se enfrentaron a un enemigo implacable que se negó a rendirse.
C1 adjective /ɪnˈhjuːmən/

Inhuman

inhumano
Meaning
lacking human qualities; cruel; brutal; savage
Example
The dictator's inhuman treatment of prisoners shocked the international community.
El trato inhumano del dictador hacia los prisioneros sorprendió a la comunidad internacional.
C2 noun /aɪər/

ire

ira, enojo
Meaning
intense anger or rage
Example
The new policy provoked the ire of the employees.
La nueva política provocó la ira de los empleados.
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.
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.
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.
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.
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.
B2 verb /ɪtʃ/

itch

picazón
Meaning
to feel an urge to scratch; to have a restless desire
Example
My skin itches from the mosquito bites.
Mi piel pica debido a las picaduras de mosquito.
C1 adjective /ɪnˈtræk.tə.bəl/

intractable

incontrolable
Meaning
Difficult or impossible to manage, control, or solve.
Example
The conflict has become an intractable problem.
El conflicto se ha convertido en un problema incontrolable.
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 /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.
C2 adjective /ɪmˈpɑːlɪtɪk/

impolitic

imprudente
Meaning
Unwise or imprudent; not showing good judgment.
Example
It would be impolitic to criticize them openly.
Sería imprudente criticarlos abiertamente.
C1 adjective /ɪˈrɛpərəbəl/

Irreparable

irreparable
Meaning
impossible to repair or fix; permanent damage that cannot be undone
Example
The accident caused irreparable damage to his spine.
El accidente causó daños irreparables en su columna vertebral.
C1 adjective /ɪnˈkɒmpɪtənt/

incompetent

incompetente
Meaning
Lacking the necessary ability or skills to do something successfully.
Example
He was fired because he was incompetent at his job.
Lo despidieron porque era incompetente en su trabajo.
C1 noun /ˈɪntərˌluːd/

interlude

interludio
Meaning
A short period of time that comes between two events; an interval.
Example
There was a brief musical interlude between the two acts of the play.
Hubo un breve interludio musical entre los dos actos de la obra.
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 verb /ɪmˈpɒvərɪʃ/

impoverish

empobrecer
Meaning
To make someone poor or reduce the quality or richness of something.
Example
The long war impoverished the entire nation.
La larga guerra empobreció a toda la nación.
C1 verb /ɪnˈkrɪmɪˌneɪt/

incriminate

incriminar
Meaning
to make someone appear guilty of a crime or wrongdoing
Example
The new evidence could incriminate the suspect in the robbery case.
La nueva evidencia podría incriminar al sospechoso en el caso de robo.
C2 noun /aɪˈkɒnəklæst/

iconoclast

iconoclasta
Meaning
A person who attacks or criticizes cherished beliefs, traditions, or institutions.
Example
He was known as an iconoclast who challenged old traditions.
Era conocido como un iconoclasta que desafiaba las viejas tradiciones.
C1 verb /ˌɪnstɪˈtjuːʃənəlaɪz/

institutionalize

institucionalizar
Meaning
to establish something as a formal institution, custom, or practice
Example
The government seeks to institutionalize environmental protection.
El gobierno busca institucionalizar la protección ambiental.
B2 noun /ɪnˈveɪʒən/

invasion

invasión
Meaning
An instance of invading a country, region, or personal space with armed force or unwelcome presence.
Example
The army prepared for the possibility of an invasion.
El ejército se preparó para la posibilidad de una invasión.
C2 adjective /ɪnˈsuːsiənt/

insouciant

despreocupado
Meaning
Showing a casual lack of concern; carefree.
Example
He gave an insouciant shrug and walked away.
Hizo un encogimiento de hombros despreocupado y se alejó.
C1 noun /ˌɪn.dɪˈsɪʒ.ən/

Indecision

indecisión; duda; vacilación
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.
Su indecisión sobre qué oferta de trabajo aceptar la llevó a perder ambas oportunidades.
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 /ˌɪnkəmˈbʌstəbl/

incombustible

incombustible
Meaning
Not capable of catching fire or burning.
Example
This material is incombustible and safe for construction.
Este material es incombustible y seguro para la construcción.
C1 adjective /ˌɪnkɒmprɪˈhɛnsəbl/

incomprehensible

incomprensible
Meaning
Impossible or very difficult to understand.
Example
The professor’s lecture was so fast it became incomprehensible.
La conferencia del profesor fue tan rápida que se volvió incomprensible.
C2 adjective /ˌɪrɪˈtriːvəbl/

irretrievable

irrecuperable
Meaning
impossible to recover or regain
Example
The documents were lost in an irretrievable way after the fire.
Los documentos se perdieron de manera irrecuperable después del incendio.
C2 verb /ˈɪndjʊˌreɪt/

indurate

endurecer
Meaning
To harden or make something physically or emotionally tough.
Example
Years of hardship indurated his spirit.
Años de dificultades induraron su espíritu.
B1 noun /ɪnˈvɛstər/

investor

inversor
Meaning
a person or organization that puts money into financial schemes, property, or business ventures with the expectation of achieving a profit
Example
The investor funded the startup with a large sum of money.
El inversor financió la startup con una gran suma de dinero.
C2 adverb /ˈɪntʃmiːl/

inchmeal

poco a poco
Meaning
Gradually, little by little.
Example
The old castle fell inchmeal into ruin.
El viejo castillo cayó poco a poco en ruinas.
B2 adjective /ɪˈmædʒ.ɪ.nər.i/

Imaginary

imaginario; ficticio; no real
Meaning
existing only in imagination; not real; fictional
Example
The child had an imaginary friend who she talked to every day.
La niña tenía un amigo imaginario con el que hablaba todos los días.
B1 adjective /ɪnˈkrɛdəbl/

incredible

increíble
Meaning
so extraordinary that it is hard to believe; amazing
Example
The view from the mountain was incredible.
La vista desde la montaña fue increíble.
C2 adjective /ɪmˈplaɪəbl/

impliable

implícito
Meaning
Capable of being implied or suggested.
Example
The meaning of the statement is not directly clear but is impliable from the context.
El significado de la declaración no es directamente claro, pero es implicable por el contexto.
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 verb ɪmˈbjuː

Imbue

Mezclar una idea o sentimiento profundamente en la mente de alguien
Meaning
Mixing some idea or feeling deeply into someone's mind
Example
The teacher tried to imbue students with a love for learning.
El profesor intentó inculcar a los estudiantes un amor por el aprendizaje.
B2 noun, verb /ˌɪnkənˈviːniəns/

inconvenience

inconveniente
Meaning
trouble or difficulty caused to someone; to cause trouble or difficulty to someone
Example
We apologize for any inconvenience caused by the delay.
Pedimos disculpas por cualquier inconveniente causado por el retraso.
C1 noun /ˌɪntərˈmiːdiˌɛri/

intermediary

intermediario
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.
El diplomático actuó como intermediario entre las dos naciones en conflicto.
B2 noun ɪnˈfleɪʃən

inflation

inflación
Meaning
A general increase in prices and fall in the purchasing value of money.
Example
Inflation erodes the purchasing power of consumers.
La inflación erosiona el poder adquisitivo de los consumidores.
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.
A2 noun, verb /ˈɪʃuː/

issue

problema, publicación, distribución
Meaning
A problem, topic, or the act of supplying or distributing something.
Example
The magazine will issue a new edition next week.
La revista publicará una nueva edición la próxima semana.
C1 adjective /ˌɪn.səˈbɔːr.dɪ.nət/

insubordinate

insubordinado
Meaning
Defiant of authority; disobedient to orders.
Example
The insubordinate employee refused to follow the manager's instructions.
El empleado insubordinado se negó a seguir las instrucciones del gerente.
C2 adjective /ɪnˈvʌlnərəbl/

invulnerable

invulnerable
Meaning
Impossible to harm, damage, or defeat.
Example
The fortress was thought to be invulnerable to attack.
Se pensaba que la fortaleza era invulnerable al ataque.
C1 noun /ɪnˈdaɪtmənt/

indictment

acusación formal
Meaning
a formal charge or accusation of a serious crime
Example
The indictment accused the company of multiple violations.
La acusación formal acusó a la empresa de múltiples violaciones.
C2 adjective /ˈɪl bred/

Ill-bred

maleducado
Meaning
lacking good manners; rude; showing poor upbringing
Example
His ill-bred behavior shocked everyone at the dinner party.
Su conducta maleducada dejó a todos sorprendidos en la cena.
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.
A1 adjective /ɪmˈpɔː.tənt/

important

importante
Meaning
Of great significance or value; likely to have a profound effect on success, survival, or well-being.
Example
Important steps must be taken to address pollution.
Se deben tomar pasos importantes para abordar la contaminación.
C2 verb /ɪnˈdʒɛst/

ingest

ingerir
Meaning
To take food, drink, or another substance into the body, usually by swallowing.
Example
The patient must ingest the medicine with water.
El paciente debe ingerir el medicamento con agua.
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.
A1 adjective /ˈɪntrəstɪŋ/ or /ˈɪntəˌrɛstɪŋ/

interesting

interesante
Meaning
Arousing curiosity or attention; holding one’s interest.
Example
The documentary about space was very interesting.
El documental sobre el espacio fue muy interesante.
C2 adjective /aɪˈdɒlətrəs/

idolatrous

idólatra
Meaning
Excessively admiring or worshipping someone or something as an idol.
Example
The king was criticized for his idolatrous devotion to wealth.
El rey fue criticado por su devoción idólatra hacia la riqueza.
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.
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 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.
C2 adjective ɪnˈfiː.zə.bəl

infeasible

invable
Meaning
Not possible to do easily or conveniently; impracticable.
Example
Restoring the forest may become infeasible if destruction continues.
Restaurar el bosque puede volverse inviable si la destrucción continúa.
C2 adjective /ˌɪntəˈrɒɡətəri/

interrogatory

interrogativo
Meaning
expressed in the form of a question; relating to questioning
Example
The lawyer’s interrogatory tone made the witness uncomfortable.
El tono interrogativo del abogado hizo sentir incómodo al testigo.
C1 adjective ɪnˈkʌm.bənt

incumbent

obligatorio
Meaning
necessary for (someone) as a duty or responsibility.
Example
It is incumbent upon all citizens to obey the law.
Es obligatorio para todos los ciudadanos obedecer la ley.
C2 noun /ˌɪnəməˈrɑːtə/

inamorata

amante
Meaning
A woman with whom someone is in love; a female lover.
Example
He wrote a poem dedicated to his inamorata.
Escribió un poema dedicado a su enamorada.
B1 noun ˈɪmpækt

impact

impacto
Meaning
A strong effect or influence; the action of one object coming forcibly into contact with another.
Example
The decision had great impact.
La decisión tuvo un gran impacto.
C1 noun /ˌɪntəkəˈnɛktɪvɪti/

interconnectivity

interconectividad
Meaning
The state of being interconnected or the degree of connectivity between components
Example
The rise of interconnectivity has transformed global communication.
El auge de la interconectividad ha transformado la comunicación global.
C1 noun /ˌɪnklɪˈneɪʃən/

inclination

inclinación
Meaning
A natural tendency or urge to act or feel in a particular way.
Example
She has an inclination towards helping others.
Ella tiene una inclinación hacia ayudar a los demás.
C2 adjective /ɪnˈvaɪələbl/

inviolable

inviolable
Meaning
never to be broken, dishonored, or violated
Example
Human rights are considered inviolable in modern democracies.
Los derechos humanos son considerados inviolables en las democracias modernas.
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 /ˈaɪ.ərn.wʊd/

Ironwood

madera de hierro
Meaning
a hard, dense wood from various trees; also the tree itself that produces small flowers
Example
The ironwood tree blooms with tiny white flowers.
El árbol de madera de hierro florece con pequeñas flores blancas.
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.
B2 noun ˌɪmplɪmenˈteɪʃən

implementation

implementación
Meaning
The process of putting a decision or plan into effect; execution.
Example
Proper implementation of policies is crucial.
La implementación adecuada de las políticas es crucial.
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 /ɪmˈpɜːrtɪnənt/

impertinent

impertinente
Meaning
rude and showing a lack of respect
Example
It was impertinent of him to question the manager's decision.
Fue impertinente de su parte cuestionar la decisión del gerente.
B2 adjective /ɪnˈfekʃəs/

infectious

infeccioso
Meaning
capable of causing infection or disease; spreading easily from one person to another; able to spread feelings or attitudes such as enthusiasm
Example
Her infectious laughter made everyone in the room smile.
Su risa infecciosa hizo sonreír a todos.
C1 verb /ˈɪmplɪˌkeɪt/

implicate

implicar
Meaning
To show someone’s involvement in a crime or wrongdoing.
Example
The evidence implicated several officials in the scandal.
La evidencia implicó a varios funcionarios en el escándalo.
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.
B2 noun /ɪnˈspekʃən/

inspection

inspección
Meaning
a careful examination of something, especially to check that it is correct or safe
Example
The building passed the safety inspection last week.
El edificio pasó la inspección de seguridad la semana pasada.
C2 adjective /ɪnˈsɛnseɪt/

insensate

insensible
Meaning
lacking physical sensation or empathy; without feeling or sensitivity
Example
The dictator's insensate cruelty shocked the world.
La crueldad insensible del dictador sorprendió al mundo.
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.
C2 noun /ɪmˈpruː.dəns/

Imprudence

imprudencia; descuido; temeridad
Meaning
the quality of being imprudent; lack of care for consequences; recklessness
Example
His financial imprudence led to bankruptcy within just two years.
Su imprudencia financiera llevó a la quiebra en solo dos años.
A2 verb /ɪnˈkluːd/

include

incluir
Meaning
to have as part of a whole; to contain or comprise
Example
The price includes all taxes.
El precio incluye todos los impuestos.
B2 verb /ɪmˈpoʊz/

impose

imponer
Meaning
to force someone to accept something; to establish or apply by authority
Example
The government imposed new taxes on luxury goods.
El gobierno impuso nuevos impuestos sobre los artículos de lujo.
C1 adjective /ɪnˈkɒmp(ə)rəbl/

incomparable

incomparable
Meaning
Without an equal in quality or excellence; matchless.
Example
The view from the mountain was incomparable.
La vista desde la montaña era incomparable.
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 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.
B2 adjective /ˌɪnstɪˈtjuːʃənl/

institutional

institucional
Meaning
Relating to an organization or established practice.
Example
The government made several institutional reforms in education.
El gobierno hizo varias reformas institucionales en la educación.
C2 adjective /ɪˈmɒdərət/

immoderate

excesivo
Meaning
excessive; beyond reasonable limits
Example
He has an immoderate love for sweets.
Él tiene un amor excesivo por los dulces.
C2 noun /ˌɪnkrʌˈsteɪʃən/

incrustation

costra
Meaning
a crust or hard coating formed on the surface of something
Example
The old pipes were blocked due to heavy incrustation of minerals.
Las viejas tuberías estaban bloqueadas debido a una fuerte incrustación de minerales.
C1 adjective /ˈɪrɪtəbl/

irritable

irritable
Meaning
easily annoyed or made angry
Example
She became irritable after working long hours without rest.
Ella se volvió irritable después de trabajar muchas horas sin descanso.
C2 adjective /ɪnˈsɛnʃənt/

insentient

insensible
Meaning
Lacking perception, consciousness, or sensation.
Example
The rock is an insentient object with no awareness.
La roca es un objeto insensible sin conciencia.
C2 adjective /ˌɪnkəmˈprɛsəbl/

incompressible

incompresible
Meaning
Not able to be pressed or squeezed into a smaller space.
Example
Liquids are generally considered incompressible.
Los líquidos generalmente se consideran incomprensibles.
B2 adjective /ˌɪn.trəˈdʌk.tər.i/

introductory

introductorio
Meaning
Serving as an introduction; preliminary or preparatory.
Example
The professor gave an introductory lecture on economics.
El profesor dio una conferencia introductoria sobre economía.
B2 noun /ˌɪmɪˈɡreɪʃən/

immigration

inmigración
Meaning
the action of coming to live permanently in a foreign country
Example
Immigration policies vary from country to country.
Las políticas de inmigración varían de un país a otro.
C2 noun /ɪmˈpʌlʃən/

impulsion

impulso
Meaning
a strong urge or drive to act; the act of impelling
Example
His impulsion to travel made him leave his job suddenly.
Su impulso de viajar lo llevó a dejar su trabajo de repente.
B2 adjective /ɪˈreɡjələr/

irregular

irregular
Meaning
not even or consistent in shape, pattern, time, or behavior; not following normal rules
Example
His attendance at work has been irregular this month.
Su asistencia al trabajo ha sido irregular este mes.
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.
B1 noun /ɪnˈtɛnʃən/

intention

intención
Meaning
A plan, aim, or purpose behind an action.
Example
Her intention was to finish the project before the deadline.
Su intención era terminar el proyecto antes de la fecha límite.
C1 adjective /ɪnˈhɛrənt/

inherent

inherente
Meaning
Existing in something as a natural, permanent, or essential quality.
Example
There are inherent risks in extreme sports.
Existen riesgos inherentes en los deportes extremos.
C2 noun /ˈɪɡ.nəˌmɪn.i/

ignominy

ignominia
Meaning
Public shame, disgrace, or dishonor.
Example
He lived the rest of his life in ignominy after the scandal.
Vivió el resto de su vida en ignominia después del escándalo.
B2 adjective /ɪnˈdɪf.ər.ənt/

indifferent

indiferente
Meaning
having no particular interest or concern; not caring one way or another
Example
She was indifferent to the outcome of the match.
Ella estaba indiferente al resultado del partido.
C2 noun /ˌɪnkrɪˈdjuːləti/

incredulity

incredulidad
Meaning
the state of being unwilling or unable to believe something
Example
She looked at him with incredulity after hearing the strange story.
Ella lo miró con incredulidad después de escuchar la extraña historia.
B2 adjective /ɪˈrɛləvənt/

Irrelevant

irrelevante
Meaning
not connected with or relevant to something; having no bearing on the matter
Example
Your past mistakes are irrelevant to this discussion.
Tus errores pasados son irrelevantes para esta discusión.
B2 adjective, noun /ɪzˈreɪli/

israeli

israelí
Meaning
relating to Israel or its people; a person from Israel
Example
She works for an Israeli company.
Ella trabaja para una empresa israelí.
B1 noun aɪˈdɛntɪti

identity

identidad
Meaning
The fact of being who or what a person or thing is; the characteristics determining who or what a person or thing is.
Example
The day reinforces our national identity.
El día refuerza nuestra identidad nacional.
B1 noun /ˌɪntərˈækʃən/

interaction

interacción mutua
Meaning
The process of people or things acting upon or influencing each other.
Example
The teacher encouraged more interaction between students.
El maestro alentó más interacción entre los estudiantes.
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.
C2 verb /ɪnˈdɒktrɪˌneɪt/

indoctrinate

adoctrinar
Meaning
To teach someone to fully accept a set of beliefs or ideas without question.
Example
The regime tried to indoctrinate the youth with propaganda.
El régimen trató de adoctrinar a la juventud con propaganda.
C2 adjective /ɪnˈɡreɪʃiˌeɪtɪŋ/

ingratiating

adulador
Meaning
Charming or flattering in a way intended to gain favor.
Example
His ingratiating smile made everyone trust him quickly.
Su sonrisa aduladora hizo que todos confiaran en él rápidamente.
C2 adjective /ɪˈlɪmɪtəbl/

illimitable

ilimitado
Meaning
Without limits or bounds.
Example
The universe is often described as illimitable.
El universo a menudo se describe como ilimitado.
C1 adjective /ɪnˈsteɪbəl/

instable

inestable
Meaning
not stable; liable to change, collapse, or fail; lacking firmness or reliability
Example
The instable political situation worried foreign investors.
La situación política inestable preocupó a los inversores extranjeros.
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 verb /ɪˈreɪdieɪt/

irradiate

irradiar
Meaning
to shine light on something; to expose to radiation; to illuminate or brighten
Example
The scientist used a lamp to irradiate the sample.
El científico usó una lámpara para irradiar la muestra.
C2 noun /ˈɪl.i.æd/

iliad

Ilíada
Meaning
An ancient Greek epic poem attributed to Homer, describing the events of the Trojan War.
Example
Students studied the Iliad to understand Greek mythology and heroism.
Los estudiantes estudiaron la Ilíada para entender la mitología griega y el heroísmo.
C1 verb /ɪmˈpɑːrt/

impart

impartir
Meaning
to make information known; to bestow or communicate
Example
The teacher imparted valuable knowledge to her students.
La maestra impartió valioso conocimiento a sus estudiantes.
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.
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.
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.
C1 adjective /ˈɪmpətənt/

impotent

impotente
Meaning
Lacking power, ability, or strength to take effective action.
Example
The citizens felt impotent against the corrupt system.
Los ciudadanos se sintieron impotentes contra el sistema corrupto.
B2 verb /ˌɪntərˈfɪər/

interfere

felicidad
Meaning
to become involved in something that is not your concern; to hinder or obstruct
Example
Parents should not interfere in their children’s personal choices.
No pudo ocultar su felicidad cuando recibió el premio.
C1 verb /ɪnˈfɛst/

infest

infestar
Meaning
to overrun in large numbers, especially so as to cause damage or discomfort
Example
The old house was infested with rats.
La vieja casa estaba infestada de ratas.
C1 noun /ɪnˈsɒm.ni.ə/

Insomnia

insomnio
Meaning
habitual sleeplessness; inability to sleep; the condition of being unable to sleep
Example
Her chronic insomnia made it difficult for her to concentrate during work hours.
Su insomnio crónico le dificultaba concentrarse durante las horas de trabajo.
C2 adverb /ɪnˈdjuːbɪtəbli/

indubitably

indudablemente
Meaning
Without a doubt; certainly.
Example
She is indubitably the best candidate for the job.
Ella es indudablemente la mejor candidata para el trabajo.