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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.
C2 noun /ˌɪn.ʌnˈdeɪ.ʃən/

inundation

inundación
Meaning
The act of flooding or overwhelming with water or things.
Example
The town suffered from a severe inundation after the heavy rains.
La ciudad sufrió una grave inundación después de las fuertes lluvias.
A2 verb /ɪnˈkluːd/

include

incluir
Meaning
to have as part of a whole; to contain or comprise
Example
The price includes all taxes.
El precio incluye todos los impuestos.
B1 verb /ɪnˈstɔːl/

install

instalar
Meaning
To place or fix equipment or software so it is ready for use.
Example
He installed the new software on his computer.
Él instaló el nuevo software en su computadora.
B2 noun ˈɪn.frəˌstrʌk.tʃər

infrastructure

infraestructura
Meaning
The basic physical and organizational structures and facilities needed for the operation of a society or enterprise.
Example
Digital infrastructure is vital for future advancements.
La infraestructura digital es vital para los avances futuros.
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.
C2 adjective /ɪnˈvaɪələbl/

inviolable

inviolable
Meaning
never to be broken, dishonored, or violated
Example
Human rights are considered inviolable in modern democracies.
Los derechos humanos son considerados inviolables en las democracias modernas.
C1 adjective /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.
B2 adjective /ɪnˈkeɪpəbəl/

incapable

incapaz
Meaning
lacking the ability, skill, or capacity to do something
Example
He is incapable of understanding complex instructions.
Es incapaz de entender instrucciones complejas.
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 /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 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 /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.
C2 noun /ˌɪkθiˈɒlədʒi/

ichthyology

icthología
Meaning
The branch of zoology that deals with fish.
Example
He pursued a degree in ichthyology at the university.
Obtuvo un título en ictiología en la universidad.
C2 noun /ˈɪntərˌveɪl/

intervale

terreno bajo a lo largo de un río, generalmente fértil y plano
Meaning
A low-lying tract of land along a river, usually fertile and flat.
Example
The farmers cultivated crops on the lush intervale by the river.
Los agricultores cultivaron cosechas en el intervalo fértil junto al río.
C2 adjective /ˈɪnˌbrɛd/

inbred

innato
Meaning
existing naturally in a person or animal; also related to reproduction within a limited community
Example
He has an inbred sense of loyalty.
Él tiene un sentido innato de lealtad.
B2 adjective /ˌɪnɪˈfɪʃənt/

Inefficient

ineficiente
Meaning
not achieving maximum productivity; wasteful of time or resources
Example
The old computer system was inefficient and wasted a lot of time.
El sistema de computadoras antiguo era ineficiente y desperdiciaba mucho tiempo.
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.
C2 verb /ɪmˈpeɪl/

impale

empalar
Meaning
to pierce or fix something with a sharp object
Example
The knight was impaled by the enemy’s spear.
El caballero fue empalado por la lanza del enemigo.
C2 noun /ɪnˈfrækʃən/

infraction

infracción
Meaning
A violation or breach of a rule, law, or agreement.
Example
The student was punished for a minor infraction of the school rules.
El estudiante fue castigado por una infracción menor de las reglas escolares.
B2 adverb /aɪˈrɒnɪkli/

ironically

irónicamente
Meaning
in a way that is contrary to what is expected or intended
Example
Ironically, the fire station burned down.
Irónicamente, la estación de bomberos se incendió.
B2 noun /ɪnˈdʒɛkʃən/

injection

inyección
Meaning
the act of introducing a substance into the body through a needle
Example
The nurse gave me an injection to prevent the infection.
La enfermera me dio una inyección para prevenir la infección.
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.
C2 noun /ɪˈmɒdəsti/

immodesty

immodestia
Meaning
lack of modesty or decency; behavior or attitude that is overly bold or improper
Example
The article was criticized for its tone of immodesty.
El artículo fue criticado por su tono de immodestia.
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.
B2 verb ˈɪmplɪmentɪd

implemented

implementado
Meaning
Put a decision or plan into effect; carried out or executed.
Example
The master plans were partially implemented.
Los planes maestros fueron implementados parcialmente.
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.
B2 adjective /ɪnˈtɒlərənt/

intolerant

intolerante
Meaning
unwilling to accept or respect beliefs or behavior different from one's own
Example
He is intolerant of any opinion that differs from his own.
Él no tolera ninguna opinión que difiera de la suya.
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.
C2 noun /ˈɪndələns/

indolence

indolencia
Meaning
Avoidance of activity or exertion; laziness.
Example
His indolence kept him from finishing the project on time.
Su indolencia le impidió terminar el proyecto a tiempo.
C1 adjective /aɪˈdɪlɪk/

idyllic

idílico y hermoso
Meaning
Like an idyll; extremely happy, peaceful, or picturesque.
Example
They enjoyed an idyllic vacation by the sea.
Disfrutaron de unas vacaciones idílicas junto al mar.
B2 noun /ˈɪm.pʌls/

Impulse

impulso; deseo súbito
Meaning
a sudden strong and unreflective urge or desire to act; a driving force or motivation
Example
She bought the expensive dress on impulse and later regretted the purchase.
Compró el vestido caro por impulso y luego lamentó la compra.
C2 adjective /ˌɪnsəˈpɔːrtəbl̩/

insupportable

insuportable
Meaning
Too extreme or difficult to be endured.
Example
The heat was insupportable during the long journey.
El calor era insoportable durante el largo viaje.
C2 adjective /ˌɪnɪkˈspiːdiənt/

inexpedient

desaconsejable
Meaning
Not advisable, suitable, or practical in the circumstances.
Example
It would be inexpedient to invest without proper research.
Sería desaconsejable invertir sin una investigación adecuada.
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.
B2 adjective /ˌɪnstɪˈtjuːʃənl/

institutional

institucional
Meaning
Relating to an organization or established practice.
Example
The government made several institutional reforms in education.
El gobierno hizo varias reformas institucionales en la educación.
C1 noun /ˌɪnkwɪˈzɪʃən/

inquisition

inquisición
Meaning
A prolonged and intense questioning or investigation, often harsh in nature.
Example
The journalist faced an inquisition from the panel about his sources.
El periodista enfrentó una inquisición del panel sobre sus fuentes.
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 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 /ˌɪnədˈvaɪzəbl/

inadvisable

desaconsejable
Meaning
Not recommended; likely to have undesirable consequences.
Example
It is inadvisable to drive in such heavy rain.
No es recomendable conducir bajo tal lluvia intensa.
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.
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.
C2 adjective /ˌɪnkəˈməʊdiəs/

incommodious

incómodo
Meaning
Uncomfortably small, cramped, or inconvenient.
Example
We had to stay in an incommodious room during the trip.
Tuvimos que quedarnos en una habitación incómoda durante el viaje.
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 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.
C2 adjective /ɪnˈeɪliənəbl/

inalienable

inalienable
Meaning
Unable to be taken away or transferred; absolute and permanent.
Example
Freedom of speech is an inalienable right.
La libertad de expresión es un derecho inalienable.
C1 noun /ˌɪn.trəˈspek.ʃən/

introspection

introspección
Meaning
The examination or observation of one's own mental and emotional processes; self-reflection.
Example
Through introspection, she gained insight into her emotions.
A través de la introspección, obtuvo una visión profunda de sus emociones.
C2 noun /aɪˈdɒlətri/

idolatry

idolatría
Meaning
The worship of idols or extreme admiration for someone or something.
Example
The priest condemned the idolatry practiced in the village.
El sacerdote condenó la idolatría practicada en el pueblo.
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 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.
B1 adjective ˈɪnəveɪtɪv

innovative

innovador
Meaning
Featuring new methods; advanced and original
Example
Innovative strategies are required to combat pollution.
Se requieren estrategias innovadoras para combatir la contaminación.
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.
B1 adjective /ɪˈmiːdiət/

immediate

inmediato
Meaning
happening or done without delay
Example
The doctor gave her immediate attention.
El doctor le dio atención inmediata.
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 ˌɪn.trəˈspek.tɪv

introspective

introspectivo
Meaning
Characterized by or given to introspection; examining one's own thoughts and feelings.
Example
Writers tend to be highly introspective individuals.
Los escritores tienden a ser individuos altamente introspectivos.
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 /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.
B2 noun ɪnˈsɛntɪvz

incentives

incentivos
Meaning
Things that motivate or encourage one to do something.
Example
Tax incentives are used to encourage investment in renewable energy.
Se utilizan incentivos fiscales para fomentar la inversión en energía renovable.
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.
B2 adjective, noun /ˌɪn.təlˈɛk.tʃu.əl/

intellectual

intelectual
Meaning
Relating to the intellect; a person who engages in critical thinking and study.
Example
She enjoys intellectual discussions about philosophy.
Ella disfruta de discusiones intelectuales sobre filosofía.
A2 preposition /ɪnˈkluːdɪŋ/

including

incluido
Meaning
used to show that someone or something is part of a larger group
Example
Many people attended the event, including students and teachers.
Muchas personas asistieron al evento, incluidos estudiantes y maestros.
B2 adjective /ˌɪntərˈmiːdiət/

intermediate

intermedio
Meaning
Coming between two things in time, place, or order; in the middle level or stage.
Example
She is taking an intermediate-level French course.
Ella está tomando un curso de francés de nivel intermedio.
B2 adjective /ˈaɪ.dəl/

Idle

perezoso; inactivo; no trabajando
Meaning
lazy; inactive; not working or being used
Example
The factory workers were idle during the strike.
Los trabajadores de la fábrica estaban inactivos durante la huelga.
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.
B2 noun, verb /ɪntʃ/

inch

pulgada / moverse lentamente
Meaning
A unit of length equal to 2.54 centimeters; or to move slowly and carefully in small amounts.
Example
She inched closer to the edge of the stage.
Ella se acercó lentamente al borde del escenario.
C2 adjective /ɪnˈsuːpərəbl/

insuperable

insuperable
Meaning
Impossible to overcome or surpass.
Example
The team faced insuperable challenges during the expedition.
El equipo enfrentó desafíos insuperables durante la expedición.
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 /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.
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.
C2 adjective /ˌɪrɪˈkɒnsɪləbl/

irreconcilable

irreconciliable
Meaning
impossible to make compatible or bring into harmony; unable to resolve differences
Example
The couple separated due to irreconcilable differences.
La pareja se separó debido a diferencias irreconciliables.
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, 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.
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.
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.
A2 verb /ɪɡˈnɔːr/

ignore

ignorar
Meaning
to refuse to take notice of; to disregard intentionally
Example
She decided to ignore the rude comments.
Ella decidió ignorar los comentarios groseros.
C2 noun /ˌɪkθiˈɒlədʒɪst/

ichthyologist

icthyólogo
Meaning
A scientist who studies fish.
Example
The ichthyologist discovered a new species of fish in the river.
El icthyólogo descubrió una nueva especie de pez en el río.
B1 noun /ɪnˌvɛs.tɪˈɡeɪ.ʃən/

investigation

investigación
Meaning
the process of inquiring into or examining something carefully to find the truth
Example
The investigation revealed new evidence about the fraud.
La investigación reveló nuevas pruebas sobre el fraude.
B2 adverb /ɪmˈpeɪʃəntli/

impatiently

impacientemente
Meaning
in a manner showing annoyance or restlessness due to delay or waiting
Example
She tapped her fingers impatiently while waiting for the reply.
Ella tamborileó los dedos impacientemente mientras esperaba la respuesta.
C2 adjective /ˌɪnkəmˈprɛsəbl/

incompressible

incompresible
Meaning
Not able to be pressed or squeezed into a smaller space.
Example
Liquids are generally considered incompressible.
Los líquidos generalmente se consideran incomprensibles.
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.
C2 verb /ɪnˈdɛmnɪfaɪ/

indemnify

indemnizar
Meaning
to compensate someone for harm or loss; to secure against future damage or cost
Example
The insurance company agreed to indemnify the client for the damages.
La compañía de seguros acordó indemnizar al cliente por los daños.
B2 adjective /ɪˈmjuːn/

immune

inmunizado
Meaning
protected from disease or from the effects of something
Example
Children who are vaccinated are immune to many diseases.
Los niños vacunados están inmunizados contra muchas enfermedades.
B1 adjective /ɪˈliː.ɡəl/

illegal

ilegal
Meaning
Not allowed by law; unlawful.
Example
It is illegal to drive without a valid license.
Es ilegal conducir sin una licencia válida.
B2 verb /ɪnˈtɛnsɪfaɪ/

intensify

intensificar
Meaning
To make something stronger, more extreme, or more forceful.
Example
The storm is expected to intensify overnight.
Se espera que la tormenta se intensifique durante la noche.
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.
B2 adjective ˈɪn.tɪ.ɡrəl

integral

integral
Meaning
Necessary to make a complete whole; essential or fundamental.
Example
Exercise is an integral part of a healthy lifestyle.
El ejercicio es una parte integral de un estilo de vida saludable.
C2 adjective /ˌɪnˈekspɜːrt/

inexpert

inexperto
Meaning
not skilled or experienced; lacking expertise
Example
The inexpert handling of the machine caused several mistakes.
El manejo inexperto de la máquina causó varios errores.
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.
C2 verb /ˌɪntərˈpoʊz/

interpose

interponer
Meaning
To place or insert between one thing and another; to intervene in a situation.
Example
He quickly interposed himself between the fighters to stop the quarrel.
Él rápidamente se interpuso entre los luchadores para detener la pelea.
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 noun /ˈɪnlɛt/

inlet

entrada
Meaning
A small arm of the sea, a lake, or a river; an opening or passage for entry.
Example
The boat entered a narrow inlet along the coast.
El bote entró en una entrada estrecha a lo largo de la costa.
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.
A2 adverb /ɪnˈdiːd/

indeed

en efecto
Meaning
used to emphasize or confirm a statement
Example
It was a long journey indeed.
Fue un largo viaje, de hecho.
C2 noun /ˌɪnəməˈrɑːtə/

inamorata

amante
Meaning
A woman with whom someone is in love; a female lover.
Example
He wrote a poem dedicated to his inamorata.
Escribió un poema dedicado a su enamorada.
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.
C2 verb /ˌɪmpɔːrˈtuːn/

importune

pedir insistentemente
Meaning
To ask someone persistently or pressingly for something
Example
The child importuned his mother for a new toy.
El niño importunó a su madre para que le comprara un juguete nuevo.
C2 conjunction /ˌɪnəzˈmʌtʃ æz/

inasmuch-as

ya que
Meaning
Because; since.
Example
He cannot attend, inasmuch as he is unwell.
Él no puede asistir, ya que está enfermo.
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.
C2 noun /ɪnˈtɛɡ.jʊ.mənt/

integument

cobertura externa
Meaning
A natural outer covering, such as skin, shell, or rind.
Example
The snake sheds its integument as it grows.
La serpiente pierde su cobertura externa a medida que crece.
C2 adjective /ˌɪndaɪˈdʒestəbəl/

Indigestible

indigerible; difícil de digerir
Meaning
difficult or impossible to digest; hard to process in the stomach
Example
The old bread became hard and indigestible.
El pan viejo se volvió duro e indigesto.
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.
B2 noun, verb /ˈɪnstɪˌtjuːt/

institute

institución
Meaning
as a noun, an organization founded for a specific purpose; as a verb, to establish or initiate
Example
The university decided to institute new rules for the library.
La universidad decidió instituir nuevas reglas para la biblioteca.
C2 adjective /ɪnˈkoʊ.ɪt/ or /ɪnˈkoʊ.eɪt/

inchoate

incompleto
Meaning
Just begun and not fully formed; rudimentary.
Example
His inchoate ideas needed more research to be developed.
Sus ideas incompletas necesitaban más investigación para ser desarrolladas.
C2 verb /ɪnˈɡrɑːft/

ingraft

implantar
Meaning
To implant or fix deeply, often used in the sense of grafting an idea or quality.
Example
The teacher tried to ingraft good manners in the students.
El maestro trató de implantar buenos modales en los estudiantes.
B2 adjective /ˌɪn.trəˈdʌk.tər.i/

introductory

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

inimitable

inimitable
Meaning
So good or unusual as to be impossible to copy; unique.
Example
His inimitable writing style made him a literary legend.
Su estilo de escritura inimitable lo convirtió en una leyenda literaria.
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 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 adjective/verb /ɪnˈkɑːrneɪt/

incarnate

encarnado
Meaning
to embody or represent in human form; in flesh
Example
She is kindness incarnate.
Ella es la bondad encarnada.
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.
C2 noun /ˈaɪdlər/

idler

holgazán
Meaning
A person who avoids work or spends time lazily.
Example
He was known as an idler who wasted his days.
Él era conocido como un holgazán que desperdiciaba sus días.
C2 noun /ˈɪnroʊd/

inroad

progreso
Meaning
An advance or significant progress, often at the expense of something else.
Example
The company made significant inroads into the mobile market.
La compañía hizo avances significativos en el mercado móvil.
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 /ɪnˈkɒmp(ə)rəbl/

incomparable

incomparable
Meaning
Without an equal in quality or excellence; matchless.
Example
The view from the mountain was incomparable.
La vista desde la montaña era incomparable.
C2 adjective /ɪnˈvʌlnərəbl/

invulnerable

invulnerable
Meaning
Impossible to harm, damage, or defeat.
Example
The fortress was thought to be invulnerable to attack.
Se pensaba que la fortaleza era invulnerable al ataque.
C2 adjective ɪnˈdɒm.ɪ.tə.bəl

indomitable

indomable
Meaning
Impossible to subdue or defeat.
Example
Her indomitable spirit helped her overcome adversity.
Su espíritu indomable la ayudó a superar la adversidad.
B2 adjective /ɪnˈfɪə.ri.ər/

inferior

inferior
Meaning
Of lower quality, rank, or status.
Example
This material is inferior to the one we used before.
Este material es inferior al que usamos antes.
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 ˈɪnəveɪtɪv tuːlz

innovative tools

herramientas innovadoras
Meaning
Creative devices or advanced technologies that introduce new methods or approaches to accomplish tasks.
Example
Teachers use innovative tools to enhance classroom learning.
Los maestros utilizan herramientas innovadoras para mejorar el aprendizaje en el aula.