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B2 verb /ˌʌndərˈskɔːr/

underscore

subrayar
Meaning
to emphasize or highlight something
Example
The incident underscored the need for better safety measures.
El incidente subrayó la necesidad de mejores medidas de seguridad.
B1 verb /ˈʌpˌɡreɪd/

upgrade

actualizar
Meaning
to raise something to a higher standard, improve
Example
We decided to upgrade the software to the latest version.
Decidimos actualizar el software a la última versión.
B2 adverb /ˈʌltəmətli/

ultimately

finalmente
Meaning
in the end, after everything else
Example
Ultimately, we decided to go ahead with the project.
Finalmente, decidimos continuar con el proyecto.
B2 adjective /ʌnˈwɪl.ɪŋ/

Unwilling

reacio; reticente;
Meaning
not ready to do something; reluctant; not wanting to do
Example
He was unwilling to share his secret with anyone.
Él no quería compartir su secreto con nadie.
B2 verb /ˈjuːtɪlaɪz/

utilize

utilizar
Meaning
to make practical or effective use of something
Example
The company aims to utilize solar energy for production.
La compañía tiene como objetivo utilizar energía solar para la producción.
C1 adjective /ˌʌnɪnˈhɪbɪtɪd/

uninhibited

desinhibido
Meaning
Not restrained or restricted; free in behavior or expression.
Example
She gave an uninhibited laugh at the joke.
Ella dio una risa desinhibida al chiste.
C1 adjective /ˌʌnfɔːrθˈkʌmɪŋ/

unforthcoming

reacio
Meaning
Not willing to talk or provide information; uncooperative.
Example
The witness was unforthcoming about what he had seen.
El testigo fue reacio a hablar sobre lo que había visto.
B2 adjective /ʌnˈbæləns/

Unbalanced

desbalanceado; inestable
Meaning
not balanced; lacking stability or equilibrium; mentally unstable
Example
The unbalanced table kept wobbling.
La mesa desbalanceada seguía tambaleando.
C1 adjective /ʌnˈɡɑː.dɪd/

Unguarded

desprotegido, descuidado
Meaning
not protected or defended; careless about revealing private thoughts or information
Example
In an unguarded moment, she revealed her true feelings about the project.
En un momento sin protección, ella reveló sus verdaderos sentimientos sobre el proyecto.
B2 adjective /ˈʌpˌhɪl/

Uphill

difícil; que requiere gran esfuerzo; inclinado hacia arriba
Meaning
difficult; requiring great effort; sloping upward
Example
Learning a new language can be an uphill battle.
Aprender un nuevo idioma puede ser una batalla difícil.
C1 adjective /ˌʌnbɪˈkʌmɪŋ/

unbecoming

inadecuado
Meaning
Not proper or appropriate for a person; unsuitable.
Example
His rude behavior was unbecoming of a leader.
Su comportamiento grosero era inadecuado para un líder.
C2 noun /ˌjuːzɜːrˈpeɪʃən/

usurpation

usurpación
Meaning
The act of taking someone's power or property illegally or by force.
Example
The general's usurpation of the presidency led to political unrest.
La usurpación de la presidencia por el general condujo a disturbios políticos.
B2 adjective /ˌʌndərˈlaɪɪŋ/

underlying

subyacente
Meaning
basic or hidden but important; forming the foundation of something
Example
The underlying reason for the conflict was never addressed.
La razón subyacente para el conflicto nunca fue abordada.
C1 adjective /ʌnˈfɛtərd/

unfettered

libre
Meaning
not restricted or confined; free
Example
The artist enjoyed unfettered freedom of expression.
El artista disfrutó de la libertad ilimitada de expresión.
A2 adjective /ˈjuːʒəl/

usual

habitual
Meaning
habitually or typically occurring or done
Example
It’s our usual meeting spot.
Es nuestro lugar habitual de reuniones.
B1 adjective /ʌnˈnoʊn/

Unknown

desconocido
Meaning
not known or identified; unfamiliar
Example
The author of this letter remains unknown.
El autor de esta carta sigue siendo desconocido.
B2 adjective /ʌnˈiːzi/

Uneasy

inquieto; ansioso; incómodo
Meaning
worried; anxious; uncomfortable; restless
Example
She felt uneasy about walking alone at night.
Ella se sentía inquieta al caminar sola de noche.
C1 adjective /ˌʌnfɔːrˈsiːn/

unforeseen

inesperado
Meaning
Not anticipated or predicted; unexpected.
Example
The project faced unforeseen challenges that delayed its completion.
El proyecto enfrentó desafíos imprevistos que retrasaron su finalización.
C1 verb /ˌʌndərˈsteɪt/

understate

minimizar
Meaning
To describe something as being less important or serious than it really is.
Example
He tends to understate his achievements.
Él tiende a restar importancia a sus logros.
C1 noun ˈʌp.raɪ.zɪŋ

uprising

levantamiento
Meaning
An act of resistance or rebellion; a revolt against an authority or government.
Example
The uprising marked the beginning of the revolution.
El levantamiento marcó el comienzo de la revolución.
A1 adjective /juːzd/

used

usado
Meaning
having already been used
Example
This is a used car.
Este es un coche usado.
C2 adjective /ˈʌndjʊleɪtɪŋ/

undulating

ondulante
Meaning
Having a smoothly rising and falling form or motion like waves.
Example
We drove through undulating hills.
Condujimos por colinas onduladas.
C1 adjective /ˌʌnəkˈnɒlɪdʒd/

unacknowledged

no reconocido
Meaning
Not recognized, admitted, or accepted; ignored or unnoticed
Example
Her contributions to the project went unacknowledged.
Sus contribuciones al proyecto pasaron desapercibidas.
C1 verb /ʌnˈnɜːrv/

unnerve

perder la confianza
Meaning
to make someone lose confidence, courage, or composure
Example
The hostile questions began to unnerve the witness.
Las preguntas hostiles comenzaron a poner nervioso al testigo.
C1 adjective ʌnˈpær.ə.leld

Unparalleled

incomparable
Meaning
Having no equal; unmatched, peerless, and supreme in quality or achievement.
Example
The unparalleled beauty of the Taj Mahal amazes visitors.
La belleza incomparable del Taj Mahal asombra a los visitantes.
C1 adjective /ʌnˈɒnəd/

unhonoured

deshonrado
Meaning
not respected or given the recognition that is deserved; treated without honor
Example
He felt unhonoured after his years of service were ignored.
Se sintió deshonrado después de que ignoraran sus años de servicio.
C1 adjective /ʌnˈtoʊld/

Untold

incontable; infinito
Meaning
very great in amount or degree; countless; immeasurable
Example
The earthquake caused untold damage to the city.
El terremoto causó daños incontables a la ciudad.
B1 adjective /ʌnˈʃʊr/

unsure

inseguro
Meaning
not certain or confident; feeling doubt
Example
She felt unsure about the decision.
Ella se sentía insegura sobre la decisión.
B1 adjective /ʌnˈfrɛndli/

unfriendly

antipático
Meaning
not kind or welcoming; hostile or cold in behavior or attitude
Example
The shop owner seemed unfriendly to new customers.
El dueño de la tienda parecía antipático con los nuevos clientes.
B2 verb /ʌnˈfəʊld/

unfold

desplegar o abrir
Meaning
to open or spread out something that was folded; to gradually reveal or develop
Example
She unfolded the letter carefully.
Ella desdobló la carta cuidadosamente.
C1 adjective /ʌnˈspiːkəbl/

unspeakable

inexpresable
Meaning
too bad or shocking to be expressed in words
Example
The survivors endured unspeakable horrors during the war.
Los sobrevivientes soportaron horrores inexpresables durante la guerra.
C1 adjective /ˌʌnˈpɑr.də.nə.bəl/

Unpardonable

imperdonable
Meaning
too bad to be forgiven; inexcusable
Example
His betrayal of trust was an unpardonable offense.
Su traición fue un delito imperdonable.
B2 adjective /ʌnˈwel.kəm/

Unwelcome

desagradable; no deseado; indeseado
Meaning
not wanted or accepted; not invited or pleasant
Example
The unwelcome news ruined their vacation plans.
Las malas noticias arruinaron sus planes de vacaciones.
C1 noun /ˈʌp.ʃɒt/

Upshot

resultado; conclusión
Meaning
the final result or outcome of a series of events; conclusion
Example
The upshot of the meeting was a decision to postpone the project.
El resultado de la reunión fue una decisión de posponer el proyecto.
C1 adjective /ʌnˈwɪtɪŋ/

unwitting

inconsciente
Meaning
Not aware of what is happening; done without realizing.
Example
She became an unwitting participant in the scam.
Se convirtió en una participante inconsciente en la estafa.
C1 adjective ʌnˈtʃɑːtɪd

uncharted

inexplorado
Meaning
Not mapped or surveyed; unknown or unexplored.
Example
The mission aimed to explore uncharted areas of the planet.
La misión tenía como objetivo explorar áreas inexploradas del planeta.
C1 adjective /ˌʌnsəˈfɪstɪˌkeɪtɪd/

unsophisticated

no sofisticado
Meaning
Lacking worldly experience, refinement, or complexity.
Example
The villagers led an unsophisticated but happy life.
Los aldeanos llevaban una vida no sofisticada pero feliz.
C2 adjective /ɜːrˈbeɪn/

urbane

urbano
Meaning
showing polished manners, refinement, and sophistication
Example
He was an urbane gentleman who charmed everyone at the party.
Era un caballero urbano que encantó a todos en la fiesta.
C1 adjective /ˌʌnprɪˈtɛnʃəs/

unpretentious

modesto
Meaning
modest; not attempting to impress others with appearance or importance
Example
She lives in an unpretentious home but is very happy.
Ella vive en una casa modesta pero es muy feliz.
B2 adjective /ʌnˈkɒmən/

uncommon

poco común
Meaning
rare, unusual, or remarkable
Example
It is uncommon to see snow in this region.
Es raro ver nieve en esta región.
B2 noun /juːˈtɪl.ə.ti/

Utility

utilidad; beneficio; servicio público
Meaning
the state of being useful, profitable, or beneficial; a public service
Example
The utility of solar panels increases with rising electricity costs.
La utilidad de los paneles solares aumenta con el aumento de los costos de electricidad.
B2 adjective /ˌʌndɪˈstɜːrbd/

Undisturbed

ininterrumpido
Meaning
not interrupted or interfered with; calm and peaceful
Example
She slept undisturbed for eight hours.
Ella durmió ininterrumpidamente durante ocho horas.
A2 adjective /ˈʌɡ.li/

Ugly

feo; repulsivo; desagradable
Meaning
unpleasant or repulsive in appearance; morally reprehensible
Example
The old building looked ugly after years of neglect.
El edificio viejo se veía feo después de años de descuido.
B2 adjective /ʌnˈsuːtəbl/

Unsuitable

inapropiado; inapto
Meaning
not fitting or appropriate for a particular purpose or situation
Example
This formal dress is unsuitable for a casual beach party.
Este vestido formal es inapropiado para una fiesta de playa casual.
C1 adjective /ʌnˈtɛnəbl/

untenable

insostenible
Meaning
not able to be maintained or defended against attack or objection
Example
The politician resigned when his position became untenable.
El político renunció cuando su posición se volvió insostenible.
C2 adjective /ʌnˈflɛdʒd/

unfledged

inexperto
Meaning
Inexperienced, immature, or not fully developed.
Example
The unfledged writer struggled to complete his first novel.
El escritor inexperto luchó por completar su primera novela.
A2 adjective /ʌnˈhel.θi/

Unhealthy

insalubre; no saludable
Meaning
harmful to health; not in good health; detrimental to well-being
Example
Eating too much fast food is unhealthy for your body.
Comer demasiada comida rápida es insalubre para tu cuerpo.
C1 adjective /ˌjuːnɪˈlætərəl/

Unilateral

unilateral
Meaning
one-sided; involving only one party
Example
The country made a unilateral decision to withdraw from the treaty.
El país tomó una decisión unilateral de retirarse del tratado.
B2 noun /ʌnˈsɜːrtənti/

Uncertainty

incertidumbre; duda o falta de certeza
Meaning
the state of being uncertain; doubt or lack of sureness
Example
The uncertainty about the weather delayed our trip.
La incertidumbre sobre el clima retrasó nuestro viaje.
C1 adjective /ʌnˈmɒdɪfaɪd/

unmodified

sin modificar
Meaning
not changed from its original form or state
Example
The data was used in its unmodified form for analysis.
Los datos se usaron en su forma sin modificar para el análisis.
A1 adverb /ʌp/

up

arriba
Meaning
towards a higher position or level
Example
He climbed up the ladder quickly.
Él subió rápidamente la escalera.
B2 verb /ɜːrdʒ/

urge

instar
Meaning
to strongly encourage or try to persuade someone to do something
Example
Doctors urge patients to exercise regularly.
Los doctores instan a los pacientes a hacer ejercicio regularmente.
C1 adjective /ˌʌnəˈfɛktɪd/

unaffected

inafectado, genuino
Meaning
Not influenced or touched by something; genuine and natural.
Example
He remained unaffected by the criticism and kept working hard.
Él permaneció sin verse afectado por la crítica y siguió trabajando duro.
B1 adverb /ʌnˈjuːʒuəli/

unusually

de manera inusual
Meaning
in a way that is not typical or expected; to an uncommon degree
Example
It was unusually cold for this time of year.
Hacía un frío inusual para esta época del año.
B1 adjective /ʌnˈplɛz.ənt/

Unpleasant

desagradable
Meaning
not giving or causing pleasure; disagreeable
Example
The medicine had an unpleasant taste.
El medicamento tenía un sabor desagradable.
C1 verb /ˌʌndəˈreɪt/

underrate

subestimar
Meaning
to fail to recognize the full value or importance of something or someone
Example
Many people underrate the benefits of regular exercise.
Muchas personas subestiman los beneficios del ejercicio regular.
C1 verb /ˌʌndərˈlaɪ/

underlie

subyacer
Meaning
to be the hidden cause or basis of something
Example
Strong cultural traditions underlie the community's practices.
Las fuertes tradiciones culturales subyacen a las prácticas de la comunidad.
C2 adjective /ˌʌnprəˈpɪʃəs/

unpropitious

desfavorable
Meaning
Not giving or indicating a good chance of success; unfavorable.
Example
The team began their journey under unpropitious weather conditions.
El equipo comenzó su viaje bajo condiciones meteorológicas desfavorables.
C1 adjective ʌnˈwɔːr.rən.tɪd

unwarranted

innecesario
Meaning
Not justified or necessary; without good reason.
Example
His anger toward the staff was completely unwarranted.
Su enojo hacia el personal fue completamente innecesario.
C1 adjective /ʌnˈsəʊʃəl/

unsocial

antisocial
Meaning
not enjoying the company of others; avoiding social interaction; contrary to social norms
Example
He prefers unsocial hours so he can work alone without interruptions.
Prefiere horarios antisociales para trabajar solo.
B2 adjective /ˌʌnkənˈvɪnsɪŋ/

Unconvincing

increíble
Meaning
failing to persuade or impress; not believable or credible
Example
His excuse for being late was completely unconvincing.
Su excusa por llegar tarde era completamente increíble.
B1 adjective /ˈɜːrdʒənt/

Urgent

urgente
Meaning
requiring immediate action or attention; pressing
Example
The patient needs urgent medical attention.
El paciente necesita atención médica urgente.
C1 adjective ˌʌn.pəˈtɜːbd

unperturbed

no preocupado o perturbado por algo; calmado y compuesto
Meaning
Not worried or disturbed by something; calm and composed.
Example
She remained unperturbed despite the challenges.
Ella permaneció tranquila a pesar de los desafíos.
A1 noun /ˈʌŋkəl/

uncle

tío
Meaning
the brother of one's father or mother
Example
My uncle is visiting us next week.
Mi tío nos visitará la próxima semana.
C2 verb /ʌpˈhiːv/

upheave

levantar
Meaning
to lift or raise something forcefully; to cause to rise suddenly
Example
The workers had to upheave the heavy stone to clear the path.
Los trabajadores tuvieron que levantar la piedra pesada para despejar el camino.
B2 adjective /ˈʌl.tɪ.mət/

Ultimate

último; supremo; final
Meaning
being the best or most extreme example of its kind; final; last
Example
This is the ultimate test of your skills.
Este es el examen final de tus habilidades.
C1 adjective /ʌnˈkæni/

uncanny

extraño
Meaning
Strange or mysterious, especially in an unsettling way.
Example
She has an uncanny ability to predict the future.
Ella tiene una extraña habilidad para predecir el futuro.
C2 adjective /ˈʌŋk.tʃu.əs/

unctuous

lisonjero
Meaning
Excessively flattering or ingratiating; oily in texture.
Example
His unctuous tone made everyone uncomfortable.
Su tono lisonjero hizo que todos se sintieran incómodos.
C1 adjective /ʌnˈtʌtʃəbəl/

Untouchable

intocable; más allá de la crítica o el ataque
Meaning
not able to be touched or affected; beyond criticism or attack
Example
The CEO seemed untouchable despite the scandal.
El CEO parecía intocable a pesar del escándalo.
B2 adjective /ʌnˈwaɪz/

unwise

imprudente
Meaning
Showing poor judgment; not sensible or prudent.
Example
It would be unwise to invest all your money in one company.
Sería imprudente invertir todo tu dinero en una sola empresa.
C1 adjective /ˌjuːnɪˈsɛljʊlər/

unicellular

unicelular
Meaning
Consisting of a single cell.
Example
Amoebas are unicellular organisms.
Las amibas son organismos unicelulares.
B2 noun /ʌnˈrest/

Unrest

inquietud; disturbio; agitación social
Meaning
a state of dissatisfaction and disturbance; social or political disorder
Example
The economic crisis led to widespread social unrest.
La crisis económica llevó a una amplia inquietud social.
B1 noun /ˈjuːnjən/

Union

unión
Meaning
the action of joining or combining; a political unit formed from separate states
Example
The union of the two companies created a powerful corporation.
La unión de las dos empresas creó una poderosa corporación.
B1 verb /juˈnaɪt/

unite

unir
Meaning
to join together or combine; to bring people or things together
Example
The crisis helped unite the community.
La crisis ayudó a unir a la comunidad.
B1 noun /ʌnˈhæp.i.nəs/

unhappiness

infelicidad
Meaning
the state of being unhappy; sadness or dissatisfaction
Example
Her constant unhappiness affected everyone around her.
Su constante infelicidad afectaba a todos a su alrededor.
C1 adjective /ʌnˈhoʊli/

Unholy

impío; perverso; profano
Meaning
wicked; sinful; profane
Example
The unholy alliance between the two companies caused public outrage.
La alianza impía entre las dos compañías causó indignación pública.
C2 adjective /ʌnˈtʃeɪst/

Unchaste

inmoral; impuro;
Meaning
not celibate; having engaged in sexual relations; lacking moral purity
Example
The conservative society considered her behavior unchaste and improper.
La sociedad conservadora consideró su comportamiento inmoral e inapropiado.
B2 adjective /ˌʌnəˈweər/

Unaware

inconsciente; ajeno; sin saber
Meaning
not knowing or realizing; having no knowledge of something
Example
She was completely unaware of the danger.
Ella estaba completamente inconsciente del peligro.
C1 noun /ʌnkənˈsɜːrn/

Unconcern

desinterés
Meaning
lack of worry or interest; indifference
Example
She showed complete unconcern about the criticism.
Ella mostró completo desinterés por las críticas.
A2 noun /ˈjuːzər/

user

usuario
Meaning
a person who uses or operates something
Example
He is a frequent user of this app.
Él es un usuario frecuente de esta aplicación.
B1 adjective /ʌnˈsɜːrtən/

Uncertain

incierto
Meaning
not able to be relied on; not known or definite; not having reliable knowledge
Example
I am uncertain about my future career plans.
Estoy incierto sobre mis planes futuros de carrera.
C1 noun /juːnəˈnɪməti/

Unanimity

unanimidad
Meaning
complete agreement among all members of a group
Example
The committee reached unanimity on the new policy.
El comité alcanzó la unanimidad sobre la nueva política.
B2 adjective /juːˈnæn.ɪ.məs/

Unanimous

unánime
Meaning
fully in agreement; shared by all
Example
The committee reached a unanimous decision.
El comité tomó una decisión unánime.
B1 adjective /ˈʌpər/

upper

superior
Meaning
higher in position or rank
Example
The upper floor of the building is under renovation.
El piso superior del edificio está en renovación.
C1 adjective /ˌʌnəbˈtruːsɪv/

unobtrusive

discreto
Meaning
not attracting attention; blending in without causing notice
Example
The security cameras are designed to be unobtrusive.
Las cámaras de seguridad están diseñadas para ser discretas.
B2 adjective /ˈʌt.ɚ/

Utter

completo; absoluto; total
Meaning
complete; absolute; total
Example
The movie was an utter disaster at the box office.
La película fue un desastre total en la taquilla.
C1 verb /ʌnˈmɑːsk/

unmask

desenmascarar
Meaning
to remove a mask or covering; to reveal the true identity, nature, or intentions of someone or something
Example
The investigation helped unmask the real culprit behind the crime.
La investigación ayudó a desenmascarar al verdadero culpable del crimen.
A2 adjective /ʌnˈkʌmf.tə.bəl/

Uncomfortable

incómodo; incómoda
Meaning
causing or feeling slight pain or physical discomfort; making someone feel embarrassed, awkward, or anxious
Example
The chair was so uncomfortable that I couldn't sit in it for more than ten minutes.
La silla era tan incómoda que no pude sentarme en ella por más de diez minutos.
B1 adjective /ˈʌpˌkʌmɪŋ/

upcoming

próximo
Meaning
about to happen or appear
Example
The upcoming event will be held next week.
El próximo evento se llevará a cabo la próxima semana.
B1 adjective /ʌnˈwel/

Unwell

enfermo; indispuesto
Meaning
not in good health; feeling sick or ill
Example
She has been feeling unwell since yesterday.
Ella ha estado sintiéndose mal desde ayer.
A2 noun /ˌʌndərˈstændɪŋ/

understanding

comprensión
Meaning
the ability to grasp the meaning, significance, or nature of something
Example
Her understanding of the issue was impressive.
Su comprensión del tema fue impresionante.
B2 adjective /ˌjuːnɪˈvɜːrsəl/

Universal

universal
Meaning
applicable to all cases; existing everywhere
Example
Music is a universal language that everyone understands.
La música es un lenguaje universal que todos entienden.
C1 adjective /ʌnˈʃeɪkən/

Unshaken

inquebrantable; firme
Meaning
not disturbed or affected; firm and steady; unwavering
Example
Her faith remained unshaken despite all the challenges.
Su fe permaneció inquebrantable a pesar de todos los desafíos.
C1 adjective /ˈʌndərhænd/

underhand

engañoso
Meaning
done secretly and dishonestly; deceitful
Example
The politician was accused of using underhand tactics to win the election.
El político fue acusado de usar tácticas engañosas para ganar las elecciones.
A2 adjective /ʌnˈtaɪdi/

Untidy

desordenado; desorganizado;
Meaning
not neat or orderly; messy and disorganized
Example
Her untidy room was filled with clothes scattered everywhere.
Su habitación desordenada estaba llena de ropa esparcida por todas partes.
C1 noun /ʌpˈhiːvəl/

upheaval

upheaval
Meaning
a violent or sudden change or disruption to something
Example
The company faced a major upheaval after the sudden resignation of its CEO.
La empresa enfrentó un gran desorden tras la repentina renuncia de su CEO.
A2 preposition /əˈpɒn/

upon

sobre
Meaning
on or immediately after
Example
Upon hearing the news, he rushed to the hospital.
Al escuchar la noticia, corrió al hospital.
B2 adverb /ʌnˈwɪlɪŋli/

unwillingly

de mala gana
Meaning
in a way that shows reluctance or lack of desire; not willingly
Example
She unwillingly agreed to attend the meeting.
Ella aceptó asistir a la reunión de mala gana.
C2 adjective /ʌnˈɡeɪnli/

ungainly

torpe
Meaning
Awkward, clumsy, or lacking grace in movement or appearance.
Example
The tall boy moved in an ungainly manner.
El chico alto se movió de manera torpe.
B2 adjective /ʌnˈriːdəbl/

unreadable

ilegible
Meaning
not able to be read or understood clearly; illegible
Example
The doctor’s handwriting was completely unreadable.
La letra del médico era completamente ilegible.
C2 noun /ˈjuːnɪvəˌlɛns/

univalence

univalencia
Meaning
The state of having a single valence or combining power, especially in chemistry.
Example
Hydrogen is characterized by its univalence in chemical reactions.
El hidrógeno se caracteriza por su univalencia en las reacciones químicas.
B2 verb /ˌʌndərˈɡoʊ/

undergo

someterse
Meaning
to go through something, especially something unpleasant or difficult
Example
She had to undergo surgery to recover.
Tuvo que someterse a cirugía para recuperarse.
C1 adjective /ʌlˈtɪəriər/

ulterior

motivo oculto
Meaning
hidden or secret, often with a selfish motive
Example
He invited her with an ulterior motive.
La invitó con un motivo oculto.
A2 conjunction /ʌnˈlɛs/

unless

a menos que
Meaning
except if
Example
We won't go unless it stops raining.
No iremos a menos que deje de llover.
C1 adjective /ˈʌpərˌmoʊst/

uppermost

más alto
Meaning
situated at the highest place or most important
Example
Her family's safety was uppermost in her mind during the crisis.
La seguridad de su familia era lo más importante en su mente durante la crisis.
C2 adjective /ʌnˈstɪntɪŋ/

unstinting

generoso
Meaning
given generously without holding back
Example
She received unstinting support from her family.
Ella recibió un apoyo generoso de su familia.
B1 adjective /ʌnˈnesəseri/

Unnecessary

innecesario; innecesario
Meaning
not needed; not required; pointless
Example
The meeting was unnecessary since all decisions were already made.
La reunión fue innecesaria ya que todas las decisiones ya se habían tomado.
C2 adjective /ʌnˈsʌlid/

unsullied

inmaculado
Meaning
not spoiled or made impure; perfectly clean or pure
Example
His reputation remained unsullied despite the accusations.
Su reputación permaneció inmaculada a pesar de las acusaciones.
B2 noun /ʌnˈkɒnʃəsnəs/

unconsciousness

inconsciencia
Meaning
the state of being unaware of and unable to respond to one's surroundings
Example
After the accident, he was in a state of unconsciousness for several hours.
Después del accidente, él estuvo en estado de inconsciencia durante varias horas.
B2 adverb /ʌnˈkaɪndli/

unkindly

cruelmente
Meaning
in a cruel, harsh, or unsympathetic manner
Example
She spoke unkindly about her colleague during the meeting.
Ella habló cruelmente de su colega durante la reunión.
C2 noun /ˈʌndərlɪŋ/

underling

subordinado
Meaning
a person of low rank or importance; a subordinate
Example
The manager ordered his underlings to finish the task quickly.
El gerente ordenó a sus subordinados terminar la tarea rápidamente.
B2 noun /ˈɜː.dʒən.si/

Urgency

urgencia
Meaning
the quality of requiring immediate action or attention; pressing importance
Example
The urgency of the situation required immediate medical attention.
La urgencia de la situación requirió atención médica inmediata.
C1 adjective /juːˈbɪkwɪtəs/

ubiquitous

ubiquito
Meaning
Existing or being everywhere at the same time.
Example
Social media has become ubiquitous among young people.
Las redes sociales se han vuelto ubicuas entre los jóvenes.
B2 adjective /ˌʌnəˈvɔɪdəbəl/

Unavoidable

Inevitable; que no se puede evitar; obligatorio
Meaning
cannot be avoided; certain to happen; inevitable
Example
The meeting is unavoidable, so we must attend.
La reunión es inevitable, así que debemos asistir.
C1 adjective /ʌnˈsoʊld/

unsold

no vendido
Meaning
not sold; remaining without a buyer
Example
The unsold goods were returned to the warehouse.
Los productos no vendidos fueron devueltos al almacén.
C2 adjective /ʌnˈmɪtɪɡeɪtɪd/

unmitigated

completo
Meaning
absolute; not lessened or moderated
Example
The meeting was an unmitigated disaster.
La reunión fue un desastre completo.
B1 adjective /ʌnˈjuː.ʒu.əl/

Unusual

inusual; extraño;
Meaning
not typical; strange; different from what is normal
Example
She wore an unusual dress to the party.
Ella llevaba un vestido inusual a la fiesta.
B2 adjective /ʌnˈstɛdi/

unsteady

inestable
Meaning
not firm or stable; likely to change or fail
Example
She felt unsteady on her feet after the long journey.
Se sentía inestable después del largo viaje.
C2 adjective /ʌkˈsɔːriəs/

uxorious

excesivamente afectuoso con la esposa
Meaning
excessively fond of or submissive to one's wife
Example
He was so uxorious that he agreed with everything his wife said.
Él era tan uxorio que estuvo de acuerdo con todo lo que su esposa decía.
C2 adjective /ʌnəˈpiːzd/

unappeased

insatisfecho
Meaning
Not satisfied or calmed; still feeling discontent or anger
Example
Despite the apology, she remained unappeased.
A pesar de la disculpa, ella permaneció insatisfecha.
B2 noun /ˈʌndərˌteɪkɪŋ/

undertaking

empresa
Meaning
A task, project, or responsibility that someone agrees to do.
Example
Starting a new company is a difficult undertaking.
Empezar una nueva empresa es una empresa difícil.