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C1 adjective, noun /ˈɪnvəlɪd/ (adjective), /ɪnˈvælɪd/ (noun)

invalid

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

inconsiderate

desconsiderado
Meaning
Thoughtless; showing a lack of concern for others.
Example
It was inconsiderate of him to play loud music late at night.
Fue desconsiderado de su parte poner música alta tarde en la noche.
C1 adjective ˌɪn.təˈdɪs.ɪ.plɪ.nər.i

interdisciplinary

interdisciplinario
Meaning
Relating to more than one branch of knowledge.
Example
The interdisciplinary approach in education enhances problem-solving skills.
El enfoque interdisciplinario en la educación mejora las habilidades para resolver problemas.
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 /ɪmˈbæl.əns/

Imbalance

desequilibrio
Meaning
lack of proportion or relation between corresponding things; unequal distribution
Example
The doctor said the patient's dizziness was caused by an inner ear imbalance.
El doctor dijo que el mareo del paciente fue causado por un desequilibrio en el oído interno.
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 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.
C1 adjective /ˌɪnəˈfɛnsɪv/

inoffensive

inoffensivo
Meaning
Not likely to offend or provoke; harmless.
Example
His inoffensive remarks kept the conversation friendly.
Sus comentarios inofensivos mantuvieron la conversación amigable.
C1 adjective /ɪnˈkɒŋɡruəs/

incongruous

incongruente
Meaning
Not fitting in with or suitable for the surroundings.
Example
His jokes were incongruous during the serious meeting.
Sus chistes fueron incongruentes durante la reunión seria.
C1 adjective /ˈɜːrksəm/

irksome

molesto
Meaning
annoying or irritating
Example
Waiting in a long line is one of the most irksome tasks.
Esperar en una larga fila es una de las tareas más molestas.
C1 noun /ˈɪnsɪdəns/

incidence

incidencia
Meaning
the occurrence, rate, or frequency of something
Example
The incidence of road accidents has decreased this year.
La incidencia de accidentes de tráfico ha disminuido este año.
C1 verb /ˌɪntəˈsɛkt/

intersect

intersectar
Meaning
to cross or pass through each other
Example
The two roads intersect at the city center.
Los dos caminos se intersectan en el centro de la ciudad.
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 /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 /ˌɪnɪkˈskjuːzəbl/

inexcusable

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

intimidate

intimidar
Meaning
To frighten or overawe someone, especially to make them do what one wants.
Example
The bully tried to intimidate the smaller kids.
El matón intentó intimidar a los niños más pequeños.
C1 adjective /ɪˈmækjələt/

immaculate

inmaculado
Meaning
perfectly clean, neat, or free from flaws
Example
Her room was immaculate, with everything in its place.
Su habitación estaba inmaculada, con todo en su lugar.
C1 adjective /ɪnˈfriːkwənt/

infrequent

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

insurgent

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

inactivity

inactividad
Meaning
the state of not being active physically or mentally; lack of action
Example
Prolonged inactivity can negatively affect both physical and mental health.
La inactividad prolongada puede afectar negativamente la salud física y mental.
C1 adjective /ˌɪnækˈsɛsəbl/

inaccessible

inaccesible
Meaning
unable to be reached, entered, or understood
Example
The remote village is almost inaccessible during the rainy season.
El pueblo remoto es casi inaccesible durante la temporada de lluvias.
C1 noun /ɪmˈpjʊərəti/

impurity

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

incarcerate

encarcelar
Meaning
to imprison or confine someone
Example
The authorities incarcerated the criminal after the trial.
Las autoridades encarcelaron al criminal después del juicio.
C1 noun /ˈɪŋklɪŋ/

inkling

presentimiento
Meaning
A slight idea, hint, or suspicion about something.
Example
She had an inkling that he was planning a surprise.
Ella tenía una ligera sospecha de que él estaba planeando una sorpresa.
C1 noun /ɪˌreɡjəˈlærɪti/

irregularity

irregularidad
Meaning
lack of regularity or consistency; a deviation from what is normal, expected, or orderly
Example
The audit revealed several financial irregularities in the company’s records.
La auditoría reveló varias irregularidades financieras en los registros de la empresa.
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 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 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.
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 /ˌɪnɑːrˈtɪkjʊlət/

inarticulate

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

inexplicable

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

Infirmity

debilidad; enfermedad; fraqueza
Meaning
physical or mental weakness; a disease or ailment; frailty
Example
Despite his advanced age and various infirmities, he remained mentally sharp and alert.
A pesar de su avanzada edad y varias enfermedades, se mantuvo mentalmente agudo y alerta.
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.
C1 noun /ɪnˈkɒmpɪtəns/

incompetence

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

immediacy

inmediación, urgencia
Meaning
The quality of bringing one into direct and instant involvement with something, giving rise to a sense of urgency or excitement.
Example
The immediacy of digital communication has reshaped business operations.
La inmediatez de la comunicación digital ha transformado las operaciones comerciales.
C1 adjective /ɪˈræʃənəl/

irrational

irracional
Meaning
not logical or reasonable; lacking clear thought
Example
His fear of the dark was completely irrational.
Su miedo a la oscuridad era completamente irracional.
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 /ɪmˈpɛrɪl/

imperil

poner en peligro
Meaning
To put in danger or at risk.
Example
Reckless driving can imperil the lives of others.
La conducción imprudente puede poner en peligro la vida de otros.
C1 adjective /ɪnˈsɪstənt/

insistent

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

insinuate

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

illuminate

iluminar
Meaning
To light up or make something clearer.
Example
Streetlights illuminate the road at night.
Las farolas iluminan la carretera de noche.
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 adjective /ˌɪməˈtɪəriəl/

immaterial

inmaterial
Meaning
Not important or relevant; lacking physical substance.
Example
The judge ruled that the argument was immaterial to the case.
El juez falló que el argumento no era relevante para el caso.
C1 verb /ˌɪn.tɚˈtwaɪn/

intertwine

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

impairment

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

intellect

intelecto
Meaning
The ability to think, reason, and understand objectively.
Example
Her intellect is admired by all her colleagues.
Su intelecto es admirado por todos sus colegas.
C1 verb /ɪnˈvɪɡ.ər.eɪt/

invigorate

revitalizar
Meaning
To give strength or energy to someone or something.
Example
A morning walk can invigorate both body and mind.
Una caminata matutina puede revitalizar tanto el cuerpo como la mente.
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 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 /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 noun /ˈɪn.floʊ/

inflow

flujo
Meaning
The movement of things such as money, people, or water into a place.
Example
The inflow of tourists boosted the local economy.
El flujo de turistas impulsó la economía local.
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 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 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 noun /ɪnˌtɪmɪˈdeɪʃən/

intimidation

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

incisive

incisivo
Meaning
Intelligently analytical and clear-thinking; showing clear thought and good understanding of what is important.
Example
His incisive comments revealed the core issues.
Sus comentarios incisivos revelaron los problemas clave.
C1 adjective /ɪnˈtjuː.ɪ.tɪv/

intuitive

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

inanimate

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

intrusion

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

Illusive

ilusorio; que parece existir pero no es real; engañoso
Meaning
deceptive; appearing to exist but not real; misleading
Example
The promise of easy money proved to be illusive and misleading.
La promesa de dinero fácil resultó ser ilusoria y engañosa.
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 /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 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 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.
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.
C1 noun/verb /ˈɪnsɛns/

incense

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

Intimacy

intimidad; cercanía
Meaning
close familiarity or friendship; closeness; a private cozy atmosphere
Example
The couple valued the emotional intimacy they shared more than material possessions.
La pareja valoró más la intimidad emocional que compartieron que las posesiones materiales.
C1 adverb /ˌɪn.ədˈvɜːr.tənt.li/

Inadvertently

inadvertidamente; sin intención; por error
Meaning
without being aware of what you are doing; unintentionally; by mistake
Example
She inadvertently deleted the important file while cleaning her computer.
Ella eliminó accidentalmente el archivo importante mientras limpiaba su computadora.
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.
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 /ɪmˈplɔːzəbl/

implausible

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

insubordination

insubordinación
Meaning
Defiance of authority; refusal to obey orders.
Example
The soldier was punished for insubordination during the mission.
El soldado fue castigado por insubordinación durante la misión.
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 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 adjective /ˈaɪərnˌklæd/

ironclad

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

interrogative

interrogativo
Meaning
Relating to or conveying a question; in grammar, used to form questions.
Example
She raised an interrogative eyebrow when she heard the news.
Ella levantó una ceja interrogativa cuando escuchó la noticia.
C1 noun /ˈɪntrɪkəsi/

intricacy

complejidad
Meaning
the quality of being very detailed or complicated
Example
The intricacy of the design impressed everyone.
La complejidad del diseño impresionó a todos.
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 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 /ɪnˈtɛstɪn/

intestine

intestino
Meaning
The part of the digestive system where food is digested and absorbed, extending from the stomach to the anus.
Example
The doctor explained how nutrients are absorbed in the small intestine.
El doctor explicó cómo los nutrientes se absorben en el intestino delgado.
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 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 /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 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 /ɪmˈpɜːrsənl/

impersonal

impersonal
Meaning
not influenced by, showing, or involving personal feelings; lacking human warmth or emotion
Example
The letter was written in a very impersonal style.
La carta fue escrita en un estilo muy impersonal.
C1 noun ˌɪnfrəˈstrʌktʃərəl dɪˈveləpmənt

infrastructural development

desarrollo infraestructural
Meaning
The process of building and improving the basic physical and organizational structures and facilities needed for the operation of a society or enterprise.
Example
Infrastructural development is necessary for efficient recycling.
El desarrollo infraestructural es necesario para el reciclaje eficiente.
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.
C1 noun /ɪnˈdʌstriəsnəs/

industriousness

diligencia
Meaning
The quality of being hardworking and diligent.
Example
His industriousness earned him a promotion at work.
Su diligencia le valió una promoción en el trabajo.
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 /ɪˈneɪn/

inane

insensato, tonto
Meaning
lacking sense, meaning, or significance; silly or pointless
Example
The movie was criticized for its inane dialogue.
La película fue criticada por sus diálogos insensatos.
C1 verb /ˈɪnkjʊˌbeɪt/

incubate

incubar
Meaning
to keep eggs, cells, or organisms at the right conditions for development
Example
The hen will incubate the eggs until they hatch.
La gallina incubará los huevos hasta que eclosionen.
C1 noun ˌɪndɪˈspensəbl səˈpɔːrt

indispensable support

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

Inaugural

inaugural
Meaning
marking the beginning of something; first; opening
Example
The president delivered his inaugural speech.
El presidente dio su discurso inaugural.
C1 adjective /ɪmˈpɛtʃ.u.əs/

impetuous

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

inequity

inequidad
Meaning
Lack of fairness or justice; unequal distribution or treatment.
Example
Social inequity continues to be a global issue.
La inequidad social sigue siendo un problema global.
C1 adjective /ˈɪnərmoʊst/

Innermost

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