inseparable
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C1 adjective /ɪnˈsɛp(ə)rəbəl/

inseparable

inseparable
Meaning
Unable to be separated or always together.
Example
The two friends have been inseparable since childhood.
Los dos amigos han sido inseparables desde la infancia.
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 /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 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 verb ɪˈnɪʃɪeɪtɪd

initiated

iniciado
Meaning
Caused a process or action to begin; started something.
Example
The project was initiated to enhance marine biodiversity.
El proyecto fue iniciado para mejorar la biodiversidad marina.
C1 adjective /ɪˈrɛfjʊtəbəl/

Irrefutable

irrefutable
Meaning
impossible to deny or disprove; undeniable
Example
The evidence against him was irrefutable.
La evidencia en su contra era irrefutable.
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 /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.
C1 adjective ɪn ˈfleɪ.ʃə.ner.i

inflationary

inflacionario
Meaning
Characterized by or tending to cause monetary inflation; relating to rising prices.
Example
The government took measures to control inflationary pressures.
El gobierno tomó medidas para controlar las presiones inflacionarias.
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 noun /ɪmˈpɛd.ɪ.mənt/

impediment

obstáculo
Meaning
A hindrance or obstruction in doing something; something that prevents progress.
Example
Lack of funds is a major impediment to the project.
La falta de fondos es un gran obstáculo para el proyecto.
C1 noun /ˌɪmpɔːrˈteɪʃən/

importation

importación
Meaning
The act of bringing goods or services into a country from abroad
Example
The importation of luxury goods is strictly regulated.
La importación de productos de lujo está estrictamente regulada.
C1 noun /ˈɪnflʌks/

influx

afluencia
Meaning
A large arrival or flow of people or things.
Example
The city experienced an influx of tourists during the festival.
La ciudad experimentó una afluencia de turistas durante el festival.
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 noun /ˈɪtʃ.i.nəs/

itchiness

picazón
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.
La picazón en los ojos a menudo conduce a frotarse.
C1 adjective /ɪmˈpɛn.ɪ.trə.bəl/

impenetrable

impenetrable
Meaning
Impossible to pass through or enter; impossible to understand.
Example
The dense forest was nearly impenetrable.
El bosque denso era casi impenetrable.
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 noun ɪnˌɛv.ɪ.təˈbɪl.ɪ.ti

inevitability

inevitabilidad
Meaning
The quality of being certain to happen and impossible to avoid or prevent.
Example
The inevitability of change is a part of life.
La inevitabilidad del cambio es parte de la vida.
C1 adjective /ɪmˈpæʃənd/

impassioned

apasionado
Meaning
Filled with or showing great emotion.
Example
She gave an impassioned speech about human rights.
Ella dio un discurso apasionado sobre los derechos humanos.
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 adjective /ɪnˈseɪʃəbl̩/

insatiable

insaciable
Meaning
impossible to satisfy; always wanting more
Example
Her insatiable curiosity drove her to read every book in the library.
Su insaciable curiosidad la llevó a leer todos los libros de la biblioteca.
C1 adjective /ɪnˈveə.ri.ə.bəl/

Invariable

invariable; constante; siempre igual
Meaning
never changing; constant; always the same
Example
His invariable routine includes morning exercise and coffee.
Su rutina invariable incluye ejercicio por la mañana y café.
C1 adjective /ɪnˈflɛksəbl/

inflexible

inflexible
Meaning
Not able to bend or change; unwilling to change ideas or behavior.
Example
His inflexible attitude made negotiations difficult.
Su actitud inflexible dificultó las negociaciones.
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 /ˌɪndɪˈsaɪsɪv/

Indecisive

indeciso
Meaning
unable to make decisions quickly; hesitant; wavering
Example
She was indecisive about which university to attend.
Ella estaba indecisa sobre qué universidad asistir.
C1 adjective /ɪˈmoʊbəl/

immobile

inmóvil
Meaning
unable to move or be moved
Example
After the accident, he was immobile for weeks.
Después del accidente, estuvo inmóvil durante semanas.
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 /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.
C1 noun /ˌɪnsɪɡˈnɪfɪkəns/

insignificance

insignificancia
Meaning
The quality of being unimportant or trivial.
Example
He felt a sense of insignificance in the vast universe.
Él sintió un sentido de insignificancia en el vasto universo.
C1 noun /ɪnˈsɜːrdʒəns/

insurgence

insurgencia
Meaning
An act of rebellion or uprising against authority.
Example
The government struggled to contain the growing insurgence.
El gobierno luchó por contener la creciente insurgencia.
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 adjective /ɪnˈdetɪd/

Indebted

endeudado; agradecido
Meaning
owing money or gratitude to someone; obligated; grateful
Example
I am deeply indebted to my teacher for all her guidance.
Estoy profundamente endeudado con mi profesora por toda su orientación.
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 adjective /ɪnˈtændʒəbl/

intangible

intangible
Meaning
Unable to be touched or grasped; not having a physical presence.
Example
Trust is an intangible quality in relationships.
La confianza es una cualidad intangible en las relaciones.
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 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 /ɪˈmuː.və.bəl/

immovable

inmóvil
Meaning
Not able to be moved; fixed in position.
Example
Immovable barriers prevent change.
Las barreras inmóviles impiden el cambio.
C1 adjective /ɪnˈtɒl.ər.ə.bəl/

Intolerable

intolerable
Meaning
unable to be endured; extremely unpleasant or painful
Example
The noise from the construction site was intolerable.
El ruido de la obra de construcción era intolerable.
C1 adjective, noun /ɪnˈdɪkətɪv/

indicative

indicativo
Meaning
Serving as a sign or expression of something; in grammar, a mood used to make factual statements.
Example
His tone was indicative of his frustration.
Su tono era indicativo de su frustración.
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 /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 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 /ɪnˈdɪɡ.nə.ti/

Indignity

indignidad; humillación; deshonra;
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.
Ella se negó a sufrir la indignidad de ser registrada sin causa justificada.
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.
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 /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 /ˈɪɡ.ni.əs/

igneous

ígnea
Meaning
Formed through the cooling and solidification of magma or lava.
Example
Granite is an igneous rock commonly used in construction.
El granito es una roca ígnea que se utiliza comúnmente en la construcción.
C1 adjective /ˈɪndɪɡoʊ bluː/

Indigo-blue

azul índigo
Meaning
a deep blue color with a purplish tinge
Example
The indigo-blue sky looked magnificent at twilight.
El cielo azul índigo se veía magnífico al atardecer.
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 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 /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 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 verb /ɪnˈfrɪndʒ/

infringe

infringir
Meaning
To actively break the terms of a law, agreement, or right.
Example
Copying this software without permission will infringe copyright laws.
Copiar este software sin permiso infringirá las leyes de derechos de autor.
C1 adjective /ɪˈniː.bri.eɪ.tɪd/

inebriated

ebrio
Meaning
under the influence of alcohol; drunk
Example
He stumbled into the room completely inebriated.
Entró en la habitación completamente ebrio.
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 /ɪnˈkwɪzɪtɪv/

inquisitive

inquisitivo
Meaning
Curious or eager to learn and ask questions.
Example
The inquisitive child asked endless questions about the stars.
El niño inquisitivo hizo preguntas interminables sobre las estrellas.
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 /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 /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.
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 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.
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 adjective /ˌɪnəˈtɛntɪv/

inattentive

inattento
Meaning
not paying attention; lacking focus or concentration
Example
The inattentive student missed several important instructions.
El estudiante inattento perdió varias instrucciones importantes.
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 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 verb /ɪnˈhɪbɪt/

inhibit

inhibir
Meaning
to prevent or restrain someone or something from acting freely; to hinder
Example
Fear can inhibit personal growth.
El miedo puede inhibir el crecimiento personal.
C1 noun /ˌɪndɪɡˈneɪʃən/

indignation

indignación
Meaning
Strong displeasure or anger caused by something unjust, offensive, or insulting.
Example
Public indignation grew after the unfair verdict.
La indignación pública creció después del veredicto injusto.
C1 verb /aɪˈdiː.ə.laɪz/

idealize

idealizar
Meaning
To regard or represent something as perfect or better than it really is.
Example
Children often idealize their parents.
Los niños a menudo idealizan a sus padres.
C1 adjective ˌɪm.pəˈsɛp.tɪ.bəl

imperceptible

imperceptible
Meaning
So subtle or gradual that it is difficult to notice or perceive
Example
The changes in his behavior were imperceptible at first.
Los cambios en su comportamiento eran imperceptibles al principio.
C1 adjective /ɪmˈprɒmp.tjuː/

impromptu

imprevisto
Meaning
Done without being planned, organized, or rehearsed; spontaneous.
Example
He gave an impromptu speech at the event.
Él dio un discurso improvisado en el evento.
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 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 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.
C1 noun /ɪˈrɛlɪvənsi/

irrelevancy

irrelevancia
Meaning
the state of being unrelated or unimportant to the matter at hand
Example
The judge dismissed the argument because of its irrelevancy to the case.
El juez rechazó el argumento por su irrelevancia para el caso.
C1 adjective /ɪmˈpɜːmiəbl/

impermeable

impermeable
Meaning
Not allowing fluid or gas to pass through.
Example
The container is made of impermeable plastic.
El contenedor está hecho de plástico impermeable.
C1 adjective /ˌɪntərˈtʃeɪndʒəbl/

interchangeable

intercambiable
Meaning
able to be exchanged with each other without difference or loss of function
Example
These machine parts are interchangeable, so they can be replaced easily.
Estas piezas de la máquina son intercambiables, por lo que se pueden reemplazar fácilmente.
C1 adjective ˌɪn.tə.dʒen.əˈreɪ.ʃən.əl

intergenerational

intergeneracional, entre diferentes generaciones de una familia
Meaning
Existing or occurring between different generations of a family.
Example
Intergenerational wisdom ensures cultural continuity.
La sabiduría intergeneracional asegura la continuidad cultural.
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 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.
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 /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 adjective /ɪˈlɪsɪt/

illicit

ilícito
Meaning
Forbidden by law, rules, or custom.
Example
The police shut down the illicit drug operation.
La policía cerró la operación de drogas ilícitas.
C1 noun /ɪˈmɜː.ʃən/

immersion

inmersión
Meaning
Complete engagement in an environment or experience.
Example
Immersion in VR games makes users feel like they are inside the virtual world.
La inmersión en juegos de VR hace que los usuarios sientan como si estuvieran dentro del mundo virtual.
C1 noun ˌɪn.fɪlˈtreɪ.ʃən

infiltration

infiltración, acceso secreto
Meaning
The process of entering or gaining access to an organization or place surreptitiously.
Example
Cybersecurity prevents infiltration into sensitive data.
La ciberseguridad previene la infiltración en datos sensibles.
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.
C1 noun /ˌɪnkəmˌpætəˈbɪlɪti/

incompatibility

incompatibilidad
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.
El proyecto fracasó por la incompatibilidad entre los dos sistemas de software.
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.
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 /aɪl/

isle

pequeña isla
Meaning
A small island or peninsula, often poetic or literary.
Example
They spent their honeymoon on a beautiful tropical isle.
Pasaron su luna de miel en una hermosa isla tropical.
C1 noun /ɪmˈpɛdɪmənt/

impediments

obstáculos
Meaning
A hindrance or obstruction in doing something; things that prevent progress or achievement.
Example
Economic impediments often hinder social development.
Los obstáculos económicos a menudo dificultan el desarrollo social.
C1 adjective ɪˈneɪt

Innate

innato o natural
Meaning
Existing from birth or natural
Example
She has an innate talent for music.
Ella tiene un talento innato para la música.
C1 adverb /ˌɪn.dɪˈskrɪm.ɪ.nət.li/

Indiscriminately

indiscriminadamente
Meaning
without making careful distinctions; randomly; without discrimination
Example
The company fired employees indiscriminately without considering their performance.
La empresa despidió a los empleados indiscriminadamente sin considerar su rendimiento.
C1 adjective /ˌɪnɔːrˈɡænɪk/

inorganic

inorgánico
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.
Los compuestos inorgánicos se estudian en los laboratorios.
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 noun /ˌɪntərˌɒpərəˈbɪləti/

interoperability

interoperabilidad
Meaning
The ability of computer systems or software to exchange and make use of information.
Example
The interoperability of different software systems ensures seamless workflow.
La interoperabilidad de diferentes sistemas de software asegura un flujo de trabajo continuo.
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.
C1 verb /ˈɪnsjuleɪt/

insulate

aislar
Meaning
To protect something by covering it, especially to prevent heat, sound, or electricity from escaping or entering.
Example
The house was insulated to reduce heating costs.
La casa fue aislada para reducir los costos de calefacción.
C1 adjective /ˈɪnfəməs/

infamous

infame
Meaning
well known for some bad quality or deed
Example
The dictator was infamous for his cruelty.
El dictador era infame por su crueldad.
C1 adjective /ˌɪnkənˈsiːvəbl̩/

inconceivable

inconcebible
Meaning
Impossible to imagine or believe; beyond comprehension.
Example
It seemed inconceivable that she could finish the marathon after such little training.
Parecía inconcebible que ella pudiera terminar el maratón después de tan poco entrenamiento.
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 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 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 /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 adjective /ˌɪn.ɪˈfɛk.tʃu.əl/

ineffectual

ineficaz
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.
El liderazgo ineficaz del gerente hizo que el equipo perdiera la motivación.
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 /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.
C1 adjective /ɪnˈdʒʊəriəs/

injurious

perjudicial
Meaning
Causing or likely to cause harm or damage.
Example
Smoking is injurious to health.
Fumar es perjudicial para la salud.
C1 adjective /ɪmˈpæsɪv/

impassive

impasible
Meaning
Not showing or feeling emotion; expressionless.
Example
Despite the shocking news, she remained impassive.
A pesar de las noticias impactantes, ella permaneció impasible.
C1 adjective /ˌɪmprɪˈsaɪs/

imprecise

impreciso
Meaning
Not exact or accurate; vague.
Example
His explanation was too imprecise to be helpful.
Su explicación era demasiado imprecisa para ser útil.
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.
C1 noun /ɪnˈsæn.ə.ti/

Insanity

locura; demencia
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.
El abogado defensor argumentó que su cliente no era culpable por razón de locura.
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 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 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 /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.
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 /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.
C1 adjective /ˈɪnsjələr/

insular

limitado, relacionado con una isla
Meaning
Narrow-minded, isolated, or relating to an island.
Example
The community was criticized for its insular attitudes toward outsiders.
La comunidad fue criticada por sus actitudes insulares hacia los forasteros.
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 adjective /ɪnˈtrɛpɪd/

intrepid

intrépido
Meaning
fearless and adventurous, often used humorously
Example
The intrepid traveler explored the jungle alone.
El intrépido viajero exploró la jungla solo.
C1 adjective /ˌɪrɪˈvɜːrsəbl/

irreversible

irreversible
Meaning
Not able to be undone, changed, or reversed.
Example
The damage caused by the fire was irreversible.
El daño causado por el fuego fue irreversible.