undergo
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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.
B2 noun /ˌʌndəˈɡrædʒuət/

undergraduate

estudiante de pregrado
Meaning
a student who has not yet earned a bachelor's degree
Example
She is an undergraduate studying computer science.
Ella es una estudiante de pregrado estudiando ciencias de la computación.
B1 adjective /ʌnˈkaɪnd/

Unkind

cruel; no amable
Meaning
cruel; not nice or caring toward others
Example
It was unkind of him to make fun of her appearance.
Fue cruel de su parte hacer burla de su apariencia.
B1 adjective /ʌnˈtru/

Untrue

falso; incorrecto
Meaning
not true; false; incorrect
Example
His statement about the incident was completely untrue.
Su declaración sobre el incidente fue completamente falsa.
B1 adjective /ˌʌnɪmˈpɔːrtənt/

unimportant

sin importancia
Meaning
not having much value, significance, or influence
Example
The detail seemed unimportant compared to the main issue.
El detalle parecía sin importancia en comparación con el problema principal.
B2 verb /ˌʌndərˈɛstɪmeɪt/

underestimate

subestimar
Meaning
To judge something as less important or smaller than it really is.
Example
Never underestimate the power of teamwork.
Nunca subestimes el poder del trabajo en equipo.
C2 noun /ˈʌŋɡwənt/

unguent

ungüento
Meaning
A soothing or healing ointment applied to the skin.
Example
The doctor applied an unguent to heal the burn.
El doctor aplicó un ungüento para sanar la quemadura.
C2 adjective /juːˈʒʊəriəs/

usurious

usurero
Meaning
Charging excessively high interest rates on loans.
Example
The bank was accused of offering loans at usurious rates.
El banco fue acusado de ofrecer préstamos a tasas usureras.
C1 noun /ˌʌnbɪˈliːf/

Unbelief

incredulidad
Meaning
lack of religious belief; skepticism or doubt
Example
His unbelief in the supernatural made him a skeptic.
Su incredulidad hacia lo sobrenatural lo convirtió en un escéptico.
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.
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.
C2 adjective /ʌnˈmɪtɪɡeɪtɪd/

unmitigated

completo
Meaning
absolute; not lessened or moderated
Example
The meeting was an unmitigated disaster.
La reunión fue un desastre completo.
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.
C2 noun /ˈʌm.brə/

Umbra

sombra completa, la región oscura del centro de una mancha solar
Meaning
the fully shaded inner region of a shadow cast by an opaque object; the dark center of a sunspot
Example
During the eclipse, we stood in the moon's umbra.
Durante el eclipse, nos paramos en la umbra de la luna.
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.
C1 adjective /ʌnˈskeɪðd/

unscathed

ileso
Meaning
Without suffering any injury, damage, or harm.
Example
She escaped from the accident unscathed.
Ella escapó del accidente ilesa.
C2 noun /ˈɜːrtʃɪn/

urchin

niño travieso de la calle
Meaning
a mischievous or poorly dressed child, often from the streets
Example
The ragged urchins played by the riverbank.
Los niños callejeros con ropa rasgada jugaban junto al río.
C1 verb /ˌʌndərˈvæljuː/

undervalue

devaluar
Meaning
To assign too low a value or importance to something or someone.
Example
She felt that her boss consistently undervalued her contributions.
Ella sintió que su jefe constantemente no valoraba sus contribuciones.
B2 adjective /ʌnˈɪndʒərd/

uninjured

ileso
Meaning
Without injury; not physically harmed.
Example
All the passengers were rescued uninjured.
Todos los pasajeros fueron rescatados ilesos.
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.
C2 adjective /juːˈbɪkwɪtəs/

ubiquitious

ubicuo
Meaning
Present, appearing, or found everywhere.
Example
Smartphones have become ubiquitous in modern society.
Los teléfonos inteligentes se han vuelto ubicuos en la sociedad moderna.
C1 adjective /ʌnˈkwaɪ.ət/

Unquiet

inquieto; ansioso; perturbado
Meaning
restless; unable to remain still or quiet; anxious or troubled
Example
She spent an unquiet night worrying about the exam results.
Pasó una noche inquieta preocupada por los resultados del examen.
C1 adjective /ʌnˈsiːmli/

unseemly

indecoroso
Meaning
Not proper or appropriate in behavior or appearance; unbecoming.
Example
His unseemly remarks embarrassed everyone at the dinner table.
Sus comentarios indecorosos avergonzaron a todos en la mesa de la cena.
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 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.
B1 adjective /ʌnˈmærid/

unmarried

soltero
Meaning
Not married; single.
Example
He is thirty-five and still unmarried.
Él tiene treinta y cinco años y sigue soltero.
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.
C1 adjective /ʌnˈɜːrθli/

unearthly

sobrenatural
Meaning
Strange or unnatural in a way that seems not of this world
Example
The forest was filled with an unearthly glow.
El bosque estaba lleno de un resplandor sobrenatural.
B2 adjective /ʌn.rɪˈleɪ.tɪd/

Unrelated

irrelevante; no relacionado
Meaning
having no connection or relationship; not connected by family ties
Example
The two incidents were completely unrelated to each other.
Los dos incidentes estaban completamente no relacionados entre sí.
C1 adjective /ʌnˈsəʊʃəbl/

unsociable

poco sociable
Meaning
not enjoying the company of others; avoiding social interaction
Example
He became unsociable after moving to a new city.
Se volvió poco sociable después de mudarse a una nueva ciudad.
B2 adjective /ʌnˈrɪəl/

unreal

irreal
Meaning
not real or not based on reality; exaggerated or imaginary
Example
The experience felt unreal after the sudden news.
La experiencia se sintió irreal después de la noticia repentina.
C1 adjective /ʌnˈsɪvəl/

Uncivil

grosero; descortés;
Meaning
not polite or courteous; rude and discourteous in behavior
Example
His uncivil remarks during the meeting offended everyone present.
Sus comentarios incivilizados durante la reunión ofendieron a todos los presentes.
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 adjective /ʌnˈlaɪkli/

Unlikely

improbable; poco probable
Meaning
not likely to happen; improbable
Example
It's unlikely to rain today with such clear skies.
Es poco probable que llueva hoy con cielos tan despejados.
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.
C2 adjective /ʌnˈwəʊntɪd/

unwonted

inusitado
Meaning
Unusual, uncommon, or out of the ordinary.
Example
She spoke with an unwonted gentleness that surprised everyone.
Ella habló con una suavidad inusual que sorprendió a todos.
A1 adverb /ʌp/

up

arriba
Meaning
towards a higher position or level
Example
He climbed up the ladder quickly.
Él subió rápidamente la escalera.
C2 noun /juːˌtɪlɪˈtɛəriənɪzəm/

utilitarianism

utilitarismo
Meaning
The ethical theory that actions are right if they are useful or for the benefit of the majority.
Example
Utilitarianism suggests that we should act to maximize overall happiness.
El utilitarismo sugiere que debemos actuar para maximizar la felicidad general.
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.
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 adverb /ʌnˈdaʊtɪdli/

undoubtedly

sin duda
Meaning
without a doubt, certainly
Example
He is undoubtedly the best player on the team.
Él es sin duda el mejor jugador del equipo.
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.
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.
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 /ʌnˈkwes.tʃən.ə.bl̩/

Unquestionable

indiscutible; seguro
Meaning
not able to be disputed or doubted; certain and beyond doubt
Example
Her honesty and integrity are unquestionable qualities.
Su honestidad e integridad son cualidades indiscutibles.
C1 adjective /ʌnˈkuːθ/

uncouth

grosero
Meaning
Lacking good manners, refinement, or grace; awkward or rough.
Example
His uncouth behavior shocked the guests at the party.
Su comportamiento grosero sorprendió a los invitados en la fiesta.
B2 noun ˌjuːtɪlaɪˈzeɪʃən

utilization

utilización
Meaning
The action of making practical and effective use of something.
Example
Increased plastic utilization calls for better waste management.
El aumento de la utilización del plástico requiere una mejor gestión de los residuos.
C1 adjective /ʌnˈseɪvəri/

unsavory

desagradable
Meaning
Disagreeable, unpleasant, or morally offensive.
Example
The politician was linked to an unsavory scandal.
El político estaba vinculado a un escándalo desagradable.
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.
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 /ʌnˈspɛərɪŋ/

unsparing

implacable
Meaning
Showing no mercy or generosity; harsh or severe.
Example
The critic was unsparing in his review of the play.
El crítico fue implacable en su reseña de la obra.
C1 adjective /ˌʌnəˈdɔːrnd/

unadorned

sencillo, sin adornos
Meaning
Plain and simple; not decorated.
Example
The room was unadorned, with only a table and a chair.
La habitación estaba sencilla, con solo una mesa y una silla.
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 /ˌjuːnɪˈsɛljʊlər/

unicellular

unicelular
Meaning
Consisting of a single cell.
Example
Amoebas are unicellular organisms.
Las amibas son organismos unicelulares.
C2 verb /ˈʌndjʊleɪt/

undulate

ondular
Meaning
To move with a smooth, wave-like motion.
Example
The snake undulated across the sand.
La serpiente onduló a través de la arena.
B1 adverb /ˌʌpsaɪd ˈdaʊn/

Upside-down

al revés
Meaning
with the upper part at the bottom; in or into a reversed position
Example
The picture was hanging upside-down on the wall.
La foto estaba colgada al revés en la pared.
B2 adjective /ˌʌnrɪˈzɒlvd/

unresolved

no resuelto
Meaning
not solved or settled; remaining undecided or unclear
Example
The dispute remains unresolved despite several meetings.
La disputa sigue sin resolverse a pesar de varias reuniones.
B2 adjective /ʌnˈprɒf.ɪ.tə.bl̩/

Unprofitable

no rentable
Meaning
not yielding profit or gain; not producing financial benefit
Example
The unprofitable business was forced to close down after three years.
El negocio no rentable se vio obligado a cerrar después de tres años.
C2 adjective /ʌnˈlɛtəd/

unlettered

analfabeto
Meaning
lacking education or the ability to read and write; illiterate
Example
The unlettered villagers relied on oral traditions to preserve their history.
Los aldeanos analfabetos dependían de las tradiciones orales para preservar su historia.
A2 noun /ˌʌpˈsteəz/

Upstairs

piso superior
Meaning
on or to an upper floor of a building; the upper floor or floors
Example
She went upstairs to her bedroom to rest.
Ella subió al piso de arriba a su dormitorio para descansar.
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 noun /ˈʌp.rɔːr/

Uproar

alboroto; ruido; disturbio
Meaning
a loud and emotional noise or disturbance; public outcry
Example
The announcement caused an uproar among the students.
El anuncio causó un alboroto entre los estudiantes.
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.
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.
C1 verb /ˌʌndərˈsɛl/

undersell

vender a un precio más bajo
Meaning
to sell something at a lower price than competitors or to downplay the value of something
Example
The shop undersold its rivals by offering huge discounts.
La tienda vendió a sus rivales a un precio más bajo ofreciendo grandes descuentos.
C1 adjective /ʌnˈmaɪndfəl/

Unmindful

despreocupado; descuidado;
Meaning
not paying attention; careless; heedless
Example
She was unmindful of the danger around her.
Ella no prestaba atención al peligro a su alrededor.
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.
B2 adjective /ˌʌnɪnˈtenʃənəl/

Unintentional

no intencionado; accidental
Meaning
not done on purpose; accidental
Example
The damage to the car was unintentional.
El daño al coche fue no intencionado.
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.
C2 adjective /ʌnˈflæpəbəl/

unflappable

imperturbable
Meaning
calm and composed, especially in difficult situations
Example
Despite the crisis, he remained unflappable and confident.
A pesar de la crisis, se mantuvo imperturbable y confiado.
B2 adjective /ʌnˈbreɪkəbəl/

Unbreakable

no se puede romper o dañar; muy fuerte y duradero
Meaning
not able to be broken or damaged; very strong and durable
Example
Their friendship formed an unbreakable bond.
Su amistad formó un vínculo inquebrantable.
C1 adjective /ˌʌnrɪˈkwaɪtɪd/

unrequited

no correspondido
Meaning
Not returned or reciprocated, especially in the context of love or affection.
Example
He suffered from unrequited love for years.
Él sufrió de amor no correspondido durante años.
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.
B1 verb /ʌnˈlɒk/

unlock

desbloquear
Meaning
to open something that is locked; to make something accessible or available
Example
She used the key to unlock the door.
Usó la llave para desbloquear la puerta.
C2 verb /ʌnˈfɛtər/

unfetter

desatar
Meaning
to release from restraint or restriction; to free
Example
The new law will unfetter small businesses from excessive regulations.
La nueva ley liberará a las pequeñas empresas de regulaciones excesivas.
A1 preposition/conjunction /ʌnˈtɪl/

until

hasta
Meaning
up to the time of
Example
I will wait until you come back.
Esperaré hasta que regreses.
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.
B2 adjective /ʌnˈkwɒl.ɪ.faɪd/

Unqualified

incapacitado; no cualificado;
Meaning
not having the necessary skills or qualifications; complete or absolute
Example
He was unqualified for the engineering position due to lack of experience.
Él estaba sin cualificaciones para el puesto de ingeniería debido a la falta de experiencia.
B2 verb /ˌʌndərˈmaɪn/

undermine

socavar
Meaning
to gradually weaken or damage something or someone
Example
Constant criticism can undermine a child's confidence.
La crítica constante puede socavar la confianza de un niño.
C2 adjective /ʌnˈʌtərəbl/

unutterable

inefable
Meaning
Too great, intense, or awful to be expressed or described in words.
Example
She was filled with unutterable joy at the news of her success.
Ella estaba llena de una alegría inefable al escuchar las noticias de su éxito.
B2 noun ˈjuːnəti

unity

unidad
Meaning
The state of being united or joined as a whole.
Example
Unity among people led to victory.
La unidad entre las personas llevó a la victoria.
B2 adverb juːˈnæn.ɪ.məs.li

unanimously

unánimemente
Meaning
With the agreement of all people involved; without opposition.
Example
The proposal was unanimously accepted.
La propuesta fue aceptada unánimemente.
C1 adjective /ˌʌn.əˈdʌl.tə.reɪ.tɪd/

Unadulterated

puro
Meaning
not mixed or diluted with any different or extra elements; pure
Example
She felt unadulterated joy when she heard the news.
Sintió una alegría pura cuando escuchó la noticia.
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.
B1 adjective /ˈɜːrbən/

urban

urbano
Meaning
related to, characteristic of, or situated in a city or town
Example
Urban areas often have higher population density than rural areas.
Las áreas urbanas suelen tener una mayor densidad de población que las áreas rurales.
C1 verb /ʌnˈkɔrk/

uncork

destapar
Meaning
To remove the cork from a bottle; to open a bottle, especially of wine
Example
He uncorked the wine and poured a glass for everyone.
Destapó el vino y sirvió un vaso para todos.
B1 adjective /ʌnˈseɪf/

Unsafe

inseguro; peligroso;
Meaning
involving or causing danger or risk; not protected from harm
Example
It is unsafe to walk alone in this neighborhood at night.
Es inseguro caminar solo en este vecindario por la noche.
C1 adverb /ʌnˈnætʃrəli/

unnaturally

de manera antinatural
Meaning
in a way that is not natural or normal; excessively or strangely
Example
He smiled unnaturally, making everyone feel uncomfortable.
Sonrió de manera antinatural, haciendo que todos se sintieran incómodos.
A2 noun /ʌmˈbrɛlə/

umbrella

paraguas
Meaning
A device used for protection against rain or sun, typically consisting of a collapsible canopy mounted on a central rod.
Example
She opened her umbrella as it started to rain.
Ella abrió su paraguas cuando empezó a llover.
A1 pronoun /ʌs/

us

nosotros
Meaning
used to refer to the speaker and one or more other people as the object of a verb or preposition
Example
She gave us a gift.
Ella nos dio un regalo.
B2 adjective /ˌʌn.əkˈsep.tə.bəl/

Unacceptable

inaceptable
Meaning
not satisfactory or allowable; not acceptable
Example
The quality of work was completely unacceptable.
La calidad del trabajo era completamente inaceptable.
B2 adjective /ʌnəˈfreɪd/

unafraid

sin miedo
Meaning
Not feeling fear; brave or courageous
Example
She walked into the dark room, unafraid of what might be inside.
Ella entró en la habitación oscura, sin miedo de lo que pudiera haber dentro.
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.
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 /ˌʌnkənˈvɛnʃənl/

unconventional

no convencional
Meaning
not based on or conforming to what is generally done or believed
Example
Her unconventional approach to teaching inspired her students to think creatively.
Su enfoque de enseñanza no convencional inspiró a sus estudiantes a pensar creativamente.
C2 verb /ˌʌn.dɪˈsiːv/

undeceive

desengañar
Meaning
To free someone from a misconception or false belief.
Example
She tried to undeceive him about the false rumors.
Ella trató de desengañarlo sobre los rumores falsos.
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.
C2 adverb /ʌnˈɜːrɪŋli/

unerringly

sin cometer errores
Meaning
Without making any mistakes; always accurate
Example
The archer aimed unerringly at the target.
El arquero apuntó sin cometer errores al objetivo.
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.
B2 verb /ʌnˈveɪl/

unveil

desvelar
Meaning
to reveal or disclose something, especially in a formal manner
Example
The company will unveil a new product next week.
La compañía desvelará un nuevo producto la próxima semana.
B2 adjective /ˌʌnkənˈtroʊld/

uncontrolled

incontrolado
Meaning
not restrained or managed; lacking control
Example
The wildfire spread in an uncontrolled manner, causing widespread damage.
El incendio forestal se extendió de manera incontrolada, causando daños generalizados.
B2 adjective /ˌʌnˈkɔːrdɪneɪtɪd/

uncoordinated

descoordinado
Meaning
lacking coordination, not well-organized or clumsy in movement
Example
His movements were uncoordinated, making him prone to accidents.
Sus movimientos eran descoordinados, lo que lo hacía propenso a accidentes.
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.
A1 interjection /ʌ/

uh

eh
Meaning
a sound people make when they hesitate or are unsure what to say next.
Example
Uh, I’m not sure if that’s the right answer.
Eh, no estoy seguro de si esa es la respuesta correcta.
B2 adjective /ʌnˈnætʃərəl/

Unnatural

antinatural
Meaning
not existing in nature; artificial; forced
Example
The actor's smile looked unnatural and forced.
La sonrisa del actor parecía antinatural y forzada.
B2 verb /ʌnˈkʌvə(r)/

uncover

descubrir
Meaning
to reveal something that was hidden or secret
Example
The investigation uncovered new evidence.
La investigación descubrió nuevas pruebas.
A1 adjective /juːzd/

used

usado
Meaning
having already been used
Example
This is a used car.
Este es un coche usado.
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 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.
C2 noun /ˈʌp.wel.ɪŋ/

upwelling

Fenómeno oceanográfico que implica el movimiento de agua densa, fría y rica en nutrientes hacia la superficie del océano.
Meaning
An oceanographic phenomenon that involves wind-driven motion of dense, cooler, and nutrient-rich water towards the ocean surface.
Example
Upwelling brings nutrients to the ocean surface.
El upwelling lleva nutrientes a la superficie del océano.
C2 adjective /ʌnˈtiːtʃəbəl/

unteachable

imposible de enseñar
Meaning
not able or willing to learn; resistant to instruction or guidance
Example
He was so stubborn that he became almost unteachable.
Era tan terco que se volvió casi imposible de enseñar.
B2 adverb /ʌnˈsɜːrtənli/

uncertainly

con incertidumbre
Meaning
in a way that shows doubt or lack of certainty
Example
She glanced uncertainly at the complicated instructions.
Ella miró las instrucciones complicadas con incertidumbre.
C2 adjective /ˌʌn.rɪˈdʒɛn.ər.ət/

unregenerate

intransigente
Meaning
Not reformed or showing no signs of change; stubbornly refusing to reform or repent.
Example
He remained an unregenerate opponent of progress.
Siguió siendo un oponente intransigente del progreso.
B2 adjective /ʌnˈriːzənəbəl/

unreasonable

irrazonable
Meaning
not guided by reason or fairness; excessive or extreme beyond what is acceptable
Example
The manager made an unreasonable demand that no one could realistically meet.
El gerente hizo una exigencia irrazonable.
C2 adjective /ˌʌnɪkˈsɛpʃənəbl/

unexceptionable

irreprochable
Meaning
Not open to objection; acceptable and unobjectionable
Example
His behavior was unexceptionable throughout the event.
Su comportamiento fue irreprochable durante el evento.
C2 noun /juːˈkeɪs/

ukase

decreto
Meaning
An authoritative decree or order, especially one issued by a sovereign or government.
Example
The czar issued a ukase restricting the freedom of the press.
El zar emitió un decreto que restringía la libertad de prensa.
B2 noun /ʌnˈkaɪndnəs/

unkindness

crueldad
Meaning
lack of kindness; cruel or inconsiderate behavior
Example
His unkindness hurt her feelings deeply.
Su crueldad hirió profundamente sus sentimientos.
C1 adjective /ʌnˈfɔːltərɪŋ/

unfaltering

inquebrantable
Meaning
Steady and resolute; not weakening or hesitating
Example
She continued with unfaltering determination.
Ella continuó con una determinación inquebrantable.
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 /ʌnˈvɔɪst/

unvoiced

no expresado
Meaning
not expressed in speech; in phonetics, a sound produced without vocal cord vibration
Example
The student kept her opinion unvoiced during the meeting.
La estudiante mantuvo su opinión no expresada durante la reunión.
B2 adverb /ʌnˈnesəserəli/

Unnecessarily

innecesariamente
Meaning
to a greater extent than is needed; without necessity
Example
Don't worry unnecessarily about the exam.
No te preocupes innecesariamente por el examen.