instigator
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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.
C1 noun /ˌɪnflɛksɪˈbɪlɪti/

inflexibility

inflexibilidad
Meaning
the quality of being rigid or unwilling to change; lack of adaptability
Example
The inflexibility of the rules caused unnecessary delays.
La inflexibilidad de las reglas causó retrasos innecesarios.
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 /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 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 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 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 /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.
C1 verb /ɪnˈstɪl/

instill

instruir
Meaning
to gradually but firmly establish an idea, attitude, or habit in someone's mind
Example
Parents try to instill good values in their children.
Los padres intentan inculcar buenos valores en sus hijos.
C1 adjective /ɪnˈdʌldʒənt/

indulgent

indulgente
Meaning
Having a tendency to be overly generous or lenient with someone.
Example
The indulgent mother allowed her child to stay up late.
La madre indulgente permitió que su hijo se quedara despierto hasta tarde.
C1 adjective /ɪnˈveɪsɪv/

invasive

invasivo
Meaning
Tending to spread harmfully, intruding aggressively, or encroaching beyond proper boundaries.
Example
The doctor explained that the procedure was minimally invasive.
El doctor explicó que el procedimiento era mínimamente invasivo.
C1 adjective; noun /ɪˈmɔːrtl/

immortal

inmortal
Meaning
living forever; never dying; lasting forever in fame or memory
Example
Legends often describe heroes as immortal beings who never die.
Las leyendas describen a los héroes como inmortales.
C1 adjective /ɪmˈpʌlsɪv/

impulsive

impulsivo, de impulso
Meaning
acting suddenly without careful thought
Example
She made an impulsive decision to buy the car.
Tomó una decisión impulsiva de comprar el coche.
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 verb /ˈɪrɪˌɡeɪt/

irrigate

regar
Meaning
to supply water to land or crops; to wash out a wound with water
Example
Farmers irrigate their fields during dry seasons.
Los agricultores riegan sus campos durante la temporada seca.
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 adverb /ɪnˈvɜːrs.li/

Inversely

inversamente; en sentido opuesto
Meaning
in a way that is opposite or contrary; in reverse order or manner
Example
The price of goods is inversely related to their availability in the market.
El precio de los productos está inversamente relacionado con su disponibilidad en el mercado.
C1 verb ɪˈnɔː.ɡjə.reɪ.tɪd

inaugurated

inaugurado
Meaning
Begin or introduce (a system, policy, or period) formally.
Example
The organization was inaugurated officially.
La organización fue inaugurada oficialmente.
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 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.
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 /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 /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 /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.
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 /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 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 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, 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 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 /ɪmˈpɛər/

impair

deteriorar
Meaning
to weaken or damage something, especially a function or ability
Example
Smoking can impair your lung capacity.
Fumar puede dañar tu capacidad pulmonar.
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 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 /ˈɪnsələnt/

insolent

insolente, arrogante
Meaning
showing a rude and arrogant lack of respect
Example
The insolent student refused to follow the teacher's instructions.
El estudiante insolente se negó a seguir las instrucciones del maestro.
C1 verb /ɪmˈpiːd/

impede

impedir
Meaning
To obstruct or hinder the progress or development of something.
Example
Lack of funds can impede business growth.
La falta de fondos puede impedir el crecimiento empresarial.
C1 noun ɪnˈsɛpʃən

inception

inicio
Meaning
The establishment or starting point of an institution or activity.
Example
The inception of the company marked a new era in the industry.
La incepción de la empresa marcó una nueva era en la industria.
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 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 /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 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 noun /ˌɪrɪˌspɒnsəˈbɪləti/

irresponsibility

irresponsabilidad
Meaning
lack of responsibility or accountability; failure to act in a reliable or sensible way
Example
The accident was caused by his irresponsibility at work.
El accidente fue causado por su irresponsabilidad en el trabajo.
C1 adverb /ˈɪnwərdli/

inwardly

por dentro
Meaning
In the mind or spirit; not outwardly visible.
Example
She smiled outwardly but inwardly she was worried.
Ella sonrió por fuera, pero por dentro estaba preocupada.
C1 noun /ˌɪn.dʒəˈnjuː.ɪ.ti/

ingenuity

ingenio
Meaning
The quality of being clever, original, and inventive.
Example
His ingenuity led to groundbreaking innovations.
Su ingenio llevó a innovaciones pioneras.
C1 noun /ɪnˈdʒʌŋkʃən/

injunction

orden judicial
Meaning
A judicial order restraining a person from an action or compelling a certain act.
Example
The court issued an injunction to stop the company from polluting the river.
El tribunal emitió una orden judicial para evitar que la empresa contaminara el río.
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 adjective /ˈɪmpjəd(ə)nt/

impudent

descarado, insolente
Meaning
not showing due respect for another person; rude
Example
The impudent child talked back to the teacher.
El niño descarado le contestó al maestro.
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 verb /ɪnˈdaɪt/

indict

acusar
Meaning
to formally accuse someone of committing a serious crime
Example
The grand jury decided to indict the politician for corruption.
El gran jurado decidió acusar al político por corrupción.
C1 adverb ɪnˈtrɪn.zɪ.kli

intrinsically

intrínsecamente
Meaning
In a way that is naturally or inherently part of something's essential nature.
Example
Some people are intrinsically motivated to learn.
Algunas personas están intrínsecamente motivadas para aprender.
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 /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 noun ˈɪn.fər.əns

inference

inferencia
Meaning
A conclusion reached on the basis of evidence and reasoning; logical deduction.
Example
Scientists make inferences based on experimental data.
Los científicos hacen inferencias basadas en datos experimentales.
C1 noun ɪˌræʃ.ənˈæl.ɪ.ti

irrationality

irracionalidad, falta de lógica, irrazonabilidad
Meaning
The quality of being illogical or unreasonable; lack of rational thought.
Example
His decision was driven by complete irrationality.
Su decisión fue impulsada por una irracionalidad completa.
C1 noun /ˌɪnfɪˈdɛləti/

infidelity

infidelidad
Meaning
the act of being unfaithful to a spouse or partner
Example
Their marriage ended due to his infidelity.
Su matrimonio terminó debido a su infidelidad.
C1 noun /ɪmˈpɜːrtɪnəns/

impertinence

impertinencia
Meaning
lack of respect; rudeness
Example
The teacher was shocked by the student's impertinence.
El maestro se sorprendió por la impertinencia del estudiante.
C1 noun /ˈɪnˌmeɪt/

inmate

interno
Meaning
a person confined to an institution such as a prison or hospital
Example
The prison has over a thousand inmates.
La prisión tiene más de mil internos.
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 /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 /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.
C1 adjective /ɪˈnuːmərəbəl/

Innumerable

innumerable; incontable; infinito
Meaning
too many to be counted; countless; infinite in number
Example
There are innumerable stars in the night sky that we cannot see with our naked eyes.
Hay innumerables estrellas en el cielo nocturno que no podemos ver con nuestros ojos desnudos.
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 noun /ɪnˈsɜːʃən/

insertion

inserción
Meaning
the action of inserting something into something else
Example
The insertion of the new data was completed successfully.
La inserción de los nuevos datos se completó con éxito.
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 noun /ɪnˈkɜːrʒən/

incursion

incursión
Meaning
A sudden attack or invasion into a place or territory.
Example
The army repelled the enemy incursion at the border.
El ejército repelió la incursión enemiga en la frontera.
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 /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 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 /ɪmˌpɒsəˈbɪlɪti/

impossibility

imposibilidad
Meaning
the state or fact of being impossible; something that cannot be done or achieved
Example
Finishing the project in one day was an impossibility.
Terminar el proyecto en un día fue una imposibilidad.
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 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 adjective /ˌɪnɪkˈskjuːzəbl/

inexcusable

inexcusable
Meaning
Too bad to be justified or overlooked; unforgivable.
Example
His rude behavior was inexcusable.
Su comportamiento grosero era inexcusable.
C1 noun /ɪnˈdjuːsmənt/

inducement

inducido
Meaning
something that persuades or encourages someone to do something
Example
The company offered a bonus as an inducement to employees.
La empresa ofreció un bono como incentivo para los empleados.
C1 adjective /ɪnˈvæljʊəbl/

invaluable

invaluable
Meaning
Extremely useful or indispensable.
Example
Her advice proved invaluable to my success.
Su consejo resultó invaluable para mi éxito.
C1 adjective /ɪnˈdʌktɪv/

inductive

inductivo
Meaning
characterized by the inference of general laws from particular instances; reasoning from specific cases to general principles
Example
The scientist used inductive reasoning to form a hypothesis.
El científico usó razonamiento inductivo para formular una hipótesis.
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 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 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 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 /ɪnˈfleɪm/

inflame

inflamar
Meaning
to arouse strong feelings or provoke anger; to cause inflammation in the body
Example
The politician's remarks served to inflame public opinion.
Las declaraciones del político sirvieron para inflamar la opinión pública.
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 /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 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 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 /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 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 /ɪˈmjuː.tə.bəl/

immutable

inmutable
Meaning
Unchangeable, permanent, or fixed
Example
The laws of physics are considered immutable.
Las leyes de la física son consideradas inmutables.
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.
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 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 /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 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.
C1 adjective /ɪnˈhɪbɪtɪd/

inhibited

inhibido
Meaning
Unable to act in a relaxed and natural way, especially due to self-consciousness or restraint.
Example
He was too inhibited to express his true feelings.
Él estaba demasiado inhibido para expresar sus verdaderos sentimientos.
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 /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 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 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 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 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 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 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 /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 /ɪnˈvælɪdeɪt/

invalidate

invalidar
Meaning
To make something not valid or legally acceptable.
Example
The new evidence may invalidate the previous ruling.
La nueva evidencia puede invalidar el fallo anterior.
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 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 /ɪmˈpɜːrviəs/

impervious

impermeable
Meaning
Not allowing fluid to pass through; unable to be affected by something.
Example
The jacket is impervious to rain.
La chaqueta es impermeable a la lluvia.
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 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.
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.
C1 noun /ɪnˈækjʊrəsi/

inaccuracy

inexactitud
Meaning
lack of accuracy or precision; an incorrect or wrong detail
Example
The report contained several factual inaccuracies.
El informe contenía varias inexactitudes.
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 /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, 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 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 /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 noun /ɪnˈhɛrɪtər/

inheritor

heredero
Meaning
a person who receives money, property, or a title when someone dies
Example
She became the inheritor of her family's estate.
Ella se convirtió en la heredera de la propiedad de su familia.
C1 adjective /ˌɪndɪˈstrʌktəbl/

indestructible

indestructible
Meaning
Impossible to destroy or break.
Example
The superhero's shield was said to be indestructible.
Se dijo que el escudo del superhéroe era indestructible.
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 /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 /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 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 /ˌɪnsəˈfɪʃənsi/

insufficiency

insuficiencia
Meaning
The state of not being enough or not being adequate.
Example
The project failed due to the insufficiency of funds.
El proyecto falló debido a la insuficiencia de fondos.