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C2 noun /aɪˈoʊtə/

iota

un mínimo
Meaning
An extremely small amount.
Example
He did not show an iota of fear.
No mostró ni un mínimo de miedo.
B1 verb /ˌɪntəˈrʌpt/

interrupt

interrumpir
Meaning
to stop someone from speaking or doing something by suddenly saying or doing something
Example
She tried not to interrupt while he was speaking.
Ella intentó no interrumpir mientras él hablaba.
C2 adjective ˌɪm.pəˈtɜː.bə.bəl

imperturbable

imperturbable
Meaning
Unable to be upset or excited; not easily disturbed.
Example
His imperturbable nature made him a great leader.
Su naturaleza imperturbable lo convirtió en un gran líder.
B2 noun /ɪmˈpeɪʃəns/

impatience

impaciencia
Meaning
The state of being quickly irritated or unable to wait calmly.
Example
His impatience grew as the meeting dragged on.
Su impaciencia creció a medida que la reunión se alargaba.
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.
C2 noun /ˌɪn.trəˈɡreʃ.ən/

introgression

introducción genética
Meaning
The transfer of genetic information from one species to another through repeated backcrossing.
Example
Introgression plays a significant role in plant breeding.
La introgressión juega un papel importante en la mejora de plantas.
C2 verb /ɪmˈbruː/

imbrue

manchar
Meaning
To stain, especially with blood.
Example
His hands were imbrued with blood after the battle.
Sus manos estaban manchadas con sangre después de la batalla.
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.
B2 adjective /ɪˈlɪt.ər.ət/

Illiterate

analfabeto; iletrado; ignorante
Meaning
unable to read or write; lacking education
Example
The program aims to help illiterate adults learn to read and write.
El programa tiene como objetivo ayudar a los adultos analfabetos a aprender a leer y escribir.
A1 preposition /ɪn ˈfrʌnt əv/

in front of

delante de
Meaning
positioned before or ahead of something; facing or located at the forward side of a person or object
Example
She stood in front of the building.
Ella estaba de pie delante del edificio.
C2 adjective /ˌɪnɪkˈstrɪkəbl/

inextricable

inextricable
Meaning
Impossible to separate or escape from.
Example
The two friends shared an inextricable bond.
Los dos amigos compartieron un vínculo inextricable.
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.
C2 adjective /ɪmˈpæsɪbəl/

impassible

impasible
Meaning
Incapable of suffering or feeling pain (used mainly in theological or philosophical contexts).
Example
Some philosophers argue that God is impassible and cannot experience human emotions.
Algunos filósofos argumentan que Dios es impasible y no puede experimentar emociones humanas.
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 /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 adjective /ɪnˈvɪnsəbl/

invincible

invencible
Meaning
too powerful to be defeated or overcome
Example
The team seemed invincible after winning ten matches in a row.
El equipo parecía invencible después de ganar diez partidos consecutivos.
B2 verb ɪnˈvɛst.ɪŋ

investing

invertir
Meaning
The act of putting money into financial schemes, shares, property, or a commercial venture with the expectation of achieving a profit.
Example
Investing in stocks can generate long-term wealth.
Invertir en acciones puede generar riqueza a largo plazo.
B1 noun /ɪˌmædʒ.ɪˈneɪ.ʃən/

Imagination

imaginación; facultad creativa
Meaning
the faculty or action of forming new ideas or images not present to the senses; creative thinking
Example
Children's imagination allows them to turn a cardboard box into a spaceship or castle.
La imaginación de los niños les permite convertir una caja de cartón en una nave espacial o castillo.
B2 noun /ˈɪnstɪŋkt/

instinct

instinto
Meaning
A natural way of behaving or reacting that does not require learning.
Example
Birds build nests by instinct.
Los pájaros construyen nidos por instinto.
C2 adjective /ɪˈnɪkwɪtəs/

iniquitous

iniquo
Meaning
grossly unfair and morally wrong
Example
Slavery was one of the most iniquitous practices in history.
La esclavitud fue una de las prácticas más iniquas de la historia.
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.
B2 adverb /ɪmˈpɔːtəntli/

importantly

de manera importante
Meaning
in a way that is of great significance or value
Example
Importantly, the report highlights the need for immediate action.
De manera importante, el informe resalta la necesidad de acción inmediata.
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.
B2 noun ˌɪm.plɪˈkeɪ.ʃən

implication

implicación
Meaning
A conclusion that can be drawn from something although it is not explicitly stated; a likely consequence.
Example
The implication of climate change is severe.
La implicación del cambio climático es grave.
B2 adjective /ɪˈmædʒɪnəbl/

imaginable

imaginable
Meaning
Capable of being imagined or conceived.
Example
They offered every imaginable type of food at the festival.
Ofrecieron todo tipo de comida imaginable en el festival.
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 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 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.
B1 verb /ˈɪndʒər/

injure

lesionar
Meaning
to cause physical harm or damage to someone or something
Example
He injured his leg while playing football.
Él lesionó su pierna mientras jugaba al fútbol.
C1 adjective /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.
B2 verb /ɪnˈveɪd/

invade

invadir
Meaning
to enter a place or country forcefully, especially as an enemy
Example
The army invaded the neighboring country.
El ejército invadió el país vecino.
C2 adjective /ˌɪndɪˈfætɪɡəbl̩/

indefatigable

inagotable
Meaning
persisting tirelessly; incapable of being fatigued
Example
Her indefatigable spirit kept the team motivated during the long project.
Su espíritu inagotable mantuvo al equipo motivado durante el largo proyecto.
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 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.
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 /ˌɪn.trəˈvɜːr.ʒən/

introversion

introversión
Meaning
The tendency to be inward-looking and shy, preferring solitary activities.
Example
Her introversion made it difficult for her to enjoy large parties.
Su introversión le dificultaba disfrutar de las grandes fiestas.
C2 noun /ɪnˈtɛstəsi/

intestacy

muerte sin testamento
Meaning
The condition of dying without having made a valid will.
Example
His estate was divided according to the laws of intestacy.
Su patrimonio fue dividido según las leyes de la intestacia.
C2 adjective /ˌɪnkænˈdɛsənt/

incandescent

incandescente
Meaning
emitting light as a result of being heated; extremely bright or passionate
Example
The incandescent lamp lit up the entire hall.
La lámpara incandescente iluminó todo el salón.
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.
C2 adjective /ɪmˈprɒvɪdənt/

improvident

imprudente
Meaning
Not having or showing foresight; spending wastefully or without thought for the future.
Example
His improvident habits left him with no savings.
Sus hábitos imprudentes lo dejaron sin ahorros.
A2 noun /ˈɪm.ɪdʒ/

Image

imagen; figura; representación
Meaning
a representation of the external form of a person or thing in art; a mental picture or impression
Example
The company worked hard to improve its public image after the scandal.
La empresa trabajó duro para mejorar su imagen pública después del escándalo.
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 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 noun /ɪnˈdem.nə.ti/

Indemnity

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

ingenuous

ingenuo
Meaning
Innocent, naive, and unsuspecting; showing childlike simplicity and sincerity.
Example
Her ingenuous smile revealed her genuine kindness.
Su sonrisa ingenua reveló su genuina amabilidad.
C2 noun /ˈɪkθiəˌsɔːrz/

ichthyosaurs

ictiosaurios (un tipo de reptil marino extinto)
Meaning
Extinct marine reptiles that resembled fish and dolphins, dominant during the Mesozoic era.
Example
Ichthyosaurs were swift predators of the ancient seas.
Los ictiosaurios eran depredadores rápidos de los mares antiguos.
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.
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.
C2 noun /ˈaɪ.kɒn/

ikon

imagen religiosa o símbolo
Meaning
A religious image or symbol, especially in the Eastern Orthodox Church.
Example
The church displayed a beautifully painted ikon of the Virgin Mary.
La iglesia mostró un ícono bellamente pintado de la Virgen María.
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 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.
B2 noun /ɪnˈkluːʒən/

inclusion

inclusión
Meaning
the action or state of including or being included within a group or structure
Example
Diversity and inclusion are key values in modern workplaces.
La diversidad y la inclusión son valores clave en los lugares de trabajo modernos.
B2 adjective /ˌɪd.iˈɒt.ɪk/

Idiotic

idiota
Meaning
extremely stupid; foolish; senseless
Example
His idiotic behavior embarrassed everyone at the meeting.
Su comportamiento idiota avergonzó a todos en la reunión.
C1 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 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 /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.
A1 noun /ˌɪnfərˈmeɪʃən/

information

información
Meaning
Facts or knowledge provided or learned about something.
Example
The website provides useful information about travel destinations.
El sitio web proporciona información útil sobre destinos de viaje.
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.
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.
C2 adjective /ɪnˈkɒŋɡruənt/

incongruent

incongruente
Meaning
Not in harmony or keeping with the surroundings or other aspects.
Example
His casual outfit looked incongruent at the formal dinner.
Su atuendo casual se veía incongruente en la cena formal.
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.
C2 adjective /ɪnhɑːrˈmoʊniəs/

Inharmonious

desarmónico
Meaning
lacking harmony; discordant in sound; not in tune
Example
The inharmonious sounds from the broken piano made everyone cover their ears.
Los sonidos desarmónicos del piano roto hicieron que todos se cubrieran los oídos.
C1 adjective /ɪnˈstrʌktɪv/

instructive

instructivo
Meaning
useful and informative; providing knowledge or instruction
Example
The lecture was highly instructive and engaging.
La conferencia fue muy instructiva y atractiva.
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 /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 /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.
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.
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.
B2 adjective /ˈaɪsi/

Icy

helado; extremadamente frío; hostil
Meaning
extremely cold; covered with ice; unfriendly or hostile
Example
The icy wind made everyone shiver.
El viento helado hizo que todos temblaran.
C2 noun /ɪnˈtɜːrmənt/

interment

entierro
Meaning
The act of burying a dead body in a grave or tomb.
Example
The interment took place at the family cemetery.
El entierro tuvo lugar en el cementerio familiar.
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 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.
B2 noun /ˌɪntərˈfɪərəns/

interference

interferencia
Meaning
the action of interfering with something
Example
The radio signal was disrupted due to interference from nearby electronics.
La señal de radio fue interrumpida debido a la interferencia de dispositivos electrónicos cercanos.
C2 noun /ˌɪntərpəˈzɪʃən/

interposition

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

indolent

perezoso
Meaning
Wanting to avoid activity or exertion; lazy.
Example
The indolent cat slept in the sun all afternoon.
El gato perezoso durmió al sol toda la tarde.
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 /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 /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 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.
C2 noun /ˌɪnədˈvɜːrtəns/

inadvertence

descuido
Meaning
Failure to pay attention; carelessness.
Example
The error happened through sheer inadvertence.
El error ocurrió por pura inadvertencia.
B2 verb /ɪnˈheɪl/

inhale

inhalar
Meaning
to breathe in; to draw air into the lungs
Example
Take a deep breath and inhale slowly.
Toma una respiración profunda e inhala lentamente.
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.
A2 noun/adjective /ˌɪndɪˈvɪdʒuəl/

individual

individuo
Meaning
A single human being as distinct from a group; relating to one person.
Example
Each individual has the right to freedom of speech.
Cada individuo tiene el derecho a la libertad de expresión.
C2 noun /ɪnˈhɪərəns/

inherence

inherencia
Meaning
The state of being an essential or permanent part of something.
Example
The inherence of risk is part of every business venture.
La inherencia del riesgo es parte de cada aventura empresarial.
B2 adjective /ɪmˈpɪəriəl/

imperial

imperial
Meaning
Relating to an empire or emperor; having supreme authority.
Example
The imperial palace was a symbol of the emperor's power.
El palacio imperial era un símbolo del poder del emperador.
C1 noun /ˌɪntərˈdʒɛkʃən/

interjection

interjección
Meaning
a word or phrase used to express sudden emotion or reaction, often standing alone
Example
Words like 'wow' and 'ouch' are common interjections in English.
Palabras como 'wow' y 'ouch' son interjecciones comunes en inglés.
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.
B2 verb /ˈɪntɪɡreɪt/

integrate

integrar
Meaning
To combine or bring together into a unified whole.
Example
The new system integrates data from multiple sources.
El nuevo sistema integra datos de múltiples fuentes.
B2 noun /ɪnˈsɪstəns/

insistence

insistencia
Meaning
the act of demanding something firmly or repeatedly
Example
At his insistence, we stayed longer.
A su insistencia, nos quedamos más tiempo.
B1 verb ɪnˈvɛst

invest

invertir
Meaning
To put money, effort, time, etc. into something to make a profit or get an advantage.
Example
Investing in intellectual property can generate passive income.
Invertir en propiedad intelectual puede generar ingresos pasivos.
C2 noun /ɪmˌprɒb.əˈbɪl.ə.ti/

Improbability

improbabilidad
Meaning
the quality or state of being improbable; unlikely to be true or to happen
Example
The improbability of winning the lottery twice didn't stop her from buying tickets.
La improbabilidad de ganar la lotería dos veces no la detuvo de comprar boletos.
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.
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.
B2 verb /ˈɪl.ə.streɪt/

illustrate

ilustrar
Meaning
to explain or make something clear by using examples, pictures, or comparisons
Example
The teacher used diagrams to illustrate the concept.
El maestro utilizó diagramas para ilustrar el concepto.
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.
B2 adjective /ˌɪnsɪˈkjʊə/

insecure

inseguro
Meaning
not confident or assured; uncertain and anxious
Example
She felt insecure about her performance in the exam.
Ella se sintió insegura acerca de su desempeño en el examen.
C1 verb /ɪnˈtruːd/

intrude

interrumpir
Meaning
To enter a place or situation where one is not wanted or not invited.
Example
He felt embarrassed to intrude on their private conversation.
Él se sintió avergonzado de interrumpir su conversación privada.
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.
A2 noun/verb /ˈɪntrəst/ or /ˈɪntəˌrɛst/

interest

interés / interés financiero
Meaning
A feeling of curiosity or concern about something; or money paid for the use of borrowed money.
Example
He showed great interest in learning new languages.
Él mostró un gran interés en aprender nuevos idiomas.
B1 adjective /ɪmˈpeɪʃənt/

impatient

impaciente
Meaning
Not able to wait calmly; restless and eager for something to happen.
Example
She grew impatient while waiting in the long queue.
Ella se impacientó mientras esperaba en la larga fila.
B2 adjective ɪnˈev.ɪ.tə.bəl

inevitable

inevitable
Meaning
Certain to happen; unavoidable.
Example
Death is an inevitable part of life.
La muerte es una parte inevitable de la vida.
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.
C2 adjective /ˌɪndɪˈtɜːrmənət/

indeterminate

indeterminado
Meaning
Not exactly known, defined, or established; vague or uncertain.
Example
The project was delayed for an indeterminate amount of time.
El proyecto se retrasó por un tiempo indeterminado.
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.
C2 adjective /ˌɪnˌɑːpərˈtuːn/

inopportune

momento inoportuno
Meaning
Happening at a bad or inconvenient time.
Example
His call came at the most inopportune moment.
Su llamada llegó en el momento más inoportuno.
B2 noun ˌɪnɪˈkwɒlɪti

inequality

desigualdad
Meaning
Difference in size, degree, circumstances, etc.; lack of equality.
Example
The theme of inequality is prominent throughout the story.
El tema de la desigualdad es prominente a lo largo de la historia.
C2 adjective /ˌɪrɪˈlɪdʒəs/

irreligious

irreligioso
Meaning
Indifferent or hostile to religion
Example
Some people in the community consider him irreligious because he never attends religious services.
Algunas personas en la comunidad lo consideran irreligioso porque nunca asiste a los servicios religiosos.
A2 adjective /ɪmˈpɑːsəbl/

impossible

imposible
Meaning
not able to occur, exist, or be done
Example
It is impossible to finish this work in one day.
Es imposible terminar este trabajo en un día.
C2 noun /ɪˈreɪdiəns/

irradiance

irradiancia
Meaning
the quality of shining brightly; the intensity of light falling on a surface
Example
The irradiance of the sun at noon was overwhelming.
La irradiancia del sol al mediodía era abrumadora.
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.
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 /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.
B1 noun /ɪmˈpruːvmənt/

improvement

mejora
Meaning
the act of making something better
Example
There has been a significant improvement in his health.
Ha habido una mejora significativa en su salud.
B2 verb /ˈɪmɪteɪt/

imitate

imitar
Meaning
to copy the behavior or manner of someone or something
Example
Children often imitate their parents' behavior.
Los niños a menudo imitan el comportamiento de sus padres.
B2 noun /ˌɪnstəˈbɪləti/

instability

inestabilidad
Meaning
lack of stability or balance; tendency to change, fail, or collapse easily
Example
Political instability has slowed economic growth in the region.
La inestabilidad política ha ralentizado el crecimiento económico de la región.
C2 adjective /ɪˈræsɪbl/

irascible

irascible
Meaning
Easily angered; quick-tempered.
Example
His irascible nature often got him into trouble.
Su naturaleza irascible a menudo lo metía en problemas.
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.
C2 noun /ˈɪŋkjʊbəs/

incubus

espíritu maligno
Meaning
An oppressive or nightmarish burden; in folklore, an evil spirit that lies upon sleeping people.
Example
Debt became an incubus that weighed heavily on the family.
La deuda se convirtió en un espíritu maligno que pesaba mucho sobre la familia.
B2 noun ˌɪn.tɪˈɡreɪ.ʃən

integration

Integración. Unificación.
Meaning
The action or process of integrating; the process of combining or adding parts to make a unified whole.
Example
Integration of networks will improve global communication.
La integración de redes mejorará la comunicación global.
A2 verb /ɪnˈkri:s/

increase

aumentar
Meaning
to become or make something larger in amount, number, or degree
Example
The company plans to increase its production this year.
La empresa planea aumentar su producción este año.