Unserviceable
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C1 adjective /ʌnˈsɜːrvɪsəbəl/

Unserviceable

inservible; defectuoso
Meaning
not in working order; unable to be used; defective
Example
The old computer became unserviceable after the system crash.
La computadora vieja se volvió inservible después del fallo del sistema.
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 /ʌnˈduː/

Undue

excesivo; inapropiado; más de lo necesario o adecuado
Meaning
excessive; inappropriate; more than is necessary or proper
Example
The teacher complained about undue pressure from parents.
El maestro se quejó de la presión excesiva de los padres.
B2 adjective /ʌnˈbaɪəst/

unbiased

imparcial
Meaning
Not showing prejudice; impartial and fair.
Example
The report gave an unbiased view of the situation.
El informe dio una vista imparcial de la situación.
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 /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.
C2 noun /ˈjuːzjuːfrʌkt/

usufruct

usufructo
Meaning
The legal right to use and enjoy the benefits of someone else’s property without owning it.
Example
The tenant had the usufruct of the land but not its ownership.
El inquilino tenía el usufructo de la tierra pero no su propiedad.
B1 verb /ʌnˈræp/

unwrap

desenvolver
Meaning
remove wrapping or covering from something; reveal something gradually or clearly
Example
She carefully unwrapped the gift with excitement.
Ella desenvolvió el regalo con cuidado y emoción.
C2 adjective /ʌnˈælɔɪd/

unalloyed

puro
Meaning
Pure, complete, and not mixed with anything else.
Example
She felt unalloyed joy at the news of her success.
Ella sintió una alegría pura al recibir la noticia de su éxito.
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.
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.
B1 adjective ʌnˈplænd

unplanned

no planificado
Meaning
Not planned or arranged in advance; happening spontaneously without preparation.
Example
Unplanned urbanization contributes to environmental issues.
La urbanización no planificada contribuye a problemas ambientales.
B1 adjective /ˌʌnbɪˈliːvəbəl/

Unbelievable

increíble
Meaning
impossible to believe; extremely surprising or remarkable
Example
The magician's performance was absolutely unbelievable.
La actuación del mago fue absolutamente increíble.
C2 adjective /ʌnˈtɛmpərd/

untempered

intempérate
Meaning
not moderated or softened; lacking proper balance or control
Example
The untempered anger of the crowd caused chaos.
La ira intempérate de la multitud causó caos.
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 noun /juːˈtoʊpiə/

utopia

utopía
Meaning
An imagined perfect society or place where everything is ideal.
Example
Many philosophers dreamed of creating a utopia for humanity.
Muchos filósofos soñaron con crear una utopía para la humanidad.
B2 adjective /ʌnˌkənˈfɜːmd/

Unconfirmed

no confirmado; no verificado;
Meaning
not confirmed as true or definite; not verified or substantiated
Example
The report remains unconfirmed until we receive official verification.
El informe sigue sin confirmar hasta que recibamos la verificación oficial.
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.
C2 verb /ˈʌndərˌmæn/

underman

quedarse sin personal
Meaning
to supply with fewer workers or personnel than needed
Example
The hospital was undermanned during the flu outbreak.
El hospital estuvo con poco personal durante el brote de gripe.
A2 verb /ʌpˈdeɪt/

update

actualizar
Meaning
to make something more modern or current; to provide new information
Example
Please update your software regularly.
Por favor, actualice su software regularmente.
B2 adjective /ʌnˈkɒn.ʃəs/

Unconscious

inconsciente; desmayado
Meaning
not awake and aware of one's surroundings; done or existing without one realizing
Example
The patient was unconscious for several hours after the surgery.
El paciente estuvo inconsciente durante varias horas después de la cirugía.
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.
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.
C1 noun /ˌʌl.tɪˈmeɪ.təm/

Ultimatum

ultimátum
Meaning
a final demand or statement of terms, the rejection of which will result in retaliation
Example
The boss gave him an ultimatum: improve or be fired.
El jefe le dio un ultimátum: mejora o serás despedido.
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.
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 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.
C1 adjective /ʌnˈvaɪəbl/

unviable

inválido
Meaning
Not capable of working successfully; not feasible or practical.
Example
The project was deemed unviable due to high costs.
El proyecto fue considerado inviable debido a los altos costos.
C1 adjective ʌnɪnˈhæbɪtəbəl

uninhabitable

inhabitable
Meaning
Not suitable or safe for people to live in.
Example
Rapid urbanization can make cities uninhabitable.
La rápida urbanización puede hacer que las ciudades sean inhabitables.
C1 adjective /ʌnˈθɪŋkɪŋ/

unthinking

irreflexivo
Meaning
done without careful thought; automatic or thoughtless
Example
His unthinking remark hurt her feelings.
Su comentario irreflexivo hirió sus sentimientos.
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 verb /ʌpˈruːt/

uproot

desarraigar
Meaning
To pull something out of the ground; to remove or displace completely.
Example
They uprooted the old tree from the garden.
Ellos desenterraron el viejo árbol del jardín.
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.
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.
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.
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.
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.
B1 noun /ˈjuːs.fəl.nəs/

Usefulness

utilidad
Meaning
the quality of being useful; practical value or helpfulness
Example
The usefulness of this tool became apparent during the project.
La utilidad de esta herramienta se hizo evidente durante el proyecto.
B2 adjective /ʌnˈskɪld/

Unskilled

no cualificado; trabajador sin habilidades
Meaning
lacking technical training or ability; not requiring special skills
Example
Many unskilled workers are looking for training opportunities.
Muchos trabajadores no cualificados están buscando oportunidades de formación.
B2 adjective /ˌʌnrɪˈlaɪəbl/

Unreliable

no confiable; no se puede confiar ni depender de él
Meaning
not dependable; not able to be trusted or relied upon
Example
The old car is unreliable and breaks down frequently.
El coche viejo no es confiable y se descompone con frecuencia.
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.
B1 adjective /ʌnˈeɪ.bəl/

Unable

incapaz
Meaning
lacking the power, skill, or means to do something
Example
He was unable to attend the meeting.
Él no pudo asistir a la reunión.
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 adjective /ʌnˈiːkwəl/

Unequal

desigual; injusto;
Meaning
not the same in quantity, size, or value; not fair or just
Example
The distribution of wealth is unequal in many countries.
La distribución de la riqueza es desigual en muchos países.
C1 adjective ʌnˈmætʃt

unmatched

incomparable
Meaning
Not equaled or rivaled by any other; without equal.
Example
The freedom fighters showed unmatched bravery.
Los luchadores por la libertad demostraron valentía incomparable.
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.
A1 adverb /ˈjuː.ʒu.ə.li/

Usually

habitualmente; usualmente
Meaning
in most cases; generally; as a rule
Example
I usually wake up at 7 AM every morning.
Normalmente me despierto a las 7 AM cada mañana.
B1 adjective /ʌnˈklɪər/

unclear

poco claro
Meaning
not easy to understand; vague or ambiguous
Example
The instructions were unclear, so I asked for clarification.
Las instrucciones eran poco claras, así que pedí aclaraciones.
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 /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 /ˌʌnˈɪntrəstɪŋ/

uninteresting

aburrido
Meaning
not holding attention or curiosity; boring
Example
The lecture was uninteresting and difficult to stay focused on.
La conferencia fue aburrida y difícil de seguir.
B2 adjective /ʌnprəˈfɛʃ.ən.əl/

Unprofessional

no profesional
Meaning
not conforming to the standards expected in a particular profession
Example
His unprofessional behavior led to his dismissal from the company.
Su comportamiento no profesional llevó a su despido de la empresa.
B1 preposition, adverb, adjective /ˌʌndərˈniːθ/

underneath

debajo, bajo
Meaning
Located directly below or beneath something
Example
The keys were hidden underneath the pile of papers.
Las llaves estaban escondidas debajo de la pila de papeles.
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 /ˌʌnɪmˈplɔɪəbəl/

unemployable

desempleable
Meaning
Not able to be employed; lacking the skills or qualities necessary for employment
Example
Due to his criminal record, he was considered unemployable in most companies.
Debido a su historial criminal, fue considerado desempleable en la mayoría de las empresas.
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.
B2 adjective /ʌnˈhɜːd/

Unheard

no escuchado; desconocido
Meaning
not heard or listened to; not given a hearing; unknown or unfamiliar
Example
His complaints went unheard by the management.
Sus quejas pasaron desapercibidas por la gerencia.
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 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 /ˈjuː.sɪdʒ/

Usage

uso
Meaning
the action of using something; the way in which words are used in a language
Example
The dictionary explains the correct usage of difficult words.
El diccionario explica el uso correcto de palabras difíciles.
B2 adjective /ˈʌt.moʊst/

Utmost

máximo; extremo
Meaning
greatest; most extreme; maximum possible
Example
She showed utmost care while handling the fragile items.
Ella mostró el máximo cuidado al manejar los artículos frágiles.
B2 adjective /ʌnˈsiːn/

Unseen

invisible; no visto ni notado anteriormente
Meaning
not previously seen or noticed; invisible; hidden
Example
The unseen forces of nature can be very powerful.
Las fuerzas invisibles de la naturaleza pueden ser muy poderosas.
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 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 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.
A1 noun /ˌjuːnɪˈvɜːrsɪti/

university

universidad
Meaning
an institution of higher education and research, which grants academic degrees
Example
She is studying law at the university.
Ella está estudiando derecho en la universidad.
B1 adjective /ʌnˈpɒpjʊlə/

unpopular

impopular
Meaning
not liked or supported by many people
Example
The decision was unpopular with the public.
La decisión fue impopular entre el público.
B2 adjective /ʌnhaɪˈdʒiːnɪk/

Unhygienic

insalubre; falta de higiene adecuada
Meaning
not clean; lacking proper sanitation
Example
The restaurant was closed due to unhygienic conditions in the kitchen.
El restaurante estaba cerrado debido a condiciones insalubres en la cocina.
C1 adjective /ʌnˈkleɪmd/

Unclaimed

no reclamado; no solicitado; abandonado o sin dueño
Meaning
not claimed by anyone; not demanded or requested; abandoned or ownerless
Example
The unclaimed luggage was stored in the airport's lost property department.
El equipaje no reclamado fue almacenado en el departamento de objetos perdidos del aeropuerto.
C1 noun /ˈʌlsər/

ulcer

úlcera
Meaning
a sore on the skin or a mucous membrane that does not heal easily
Example
The doctor prescribed medicine to treat the stomach ulcer.
El médico recetó un medicamento para tratar la úlcera de estómago.
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 /ʌnˈɡreɪt.fəl/

Ungrateful

ingrato
Meaning
not feeling or showing thanks for something done or given; not appreciating kindness
Example
She felt he was ungrateful for all the help she had given him.
Ella sintió que él era ingrato por toda la ayuda que le había dado.
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.
B2 adjective /ʌnˈhɜːrt/

unhurt

ileso
Meaning
Not injured or harmed.
Example
She walked away from the accident unhurt.
Ella caminó lejos del accidente sin sufrir daño.
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.
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.
B1 adjective /ʌnˈkaʊntəbəl/

Uncountable

incontable; innumerable
Meaning
too many to be counted; innumerable; infinite in quantity
Example
There are uncountable stars in the night sky.
Hay estrellas incontables en el cielo nocturno.
C2 noun/verb /ˈʌpˌkæst/

upcast

lanzar hacia arriba
Meaning
Verb: To cast or throw upward. Noun: Something thrown or directed upward.
Example
The fisherman upcast his net into the air.
El pescador lanzó su red al aire.
C2 noun /ˌjuːnɪˈtɛəriən/

unitarian

unitario
Meaning
A person who believes that God exists as one entity rather than as a Trinity; a member of a religious denomination that emphasizes individual freedom of belief.
Example
The Unitarian church is known for its inclusive and open-minded approach.
La iglesia unitaria es conocida por su enfoque inclusivo y de mente abierta.
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.
C2 adjective ˌʌn.əˈseɪ.lə.bəl

unassailable

inexpugnable
Meaning
Unable to be attacked, questioned, or defeated.
Example
An unassailable position ensures dominance.
Una posición inexpugnable asegura la dominancia.
B1 adjective /ʌnˈlaɪk/

Unlike

diferente; no similar
Meaning
different from; not similar to
Example
Unlike his brother, he prefers quiet activities.
A diferencia de su hermano, él prefiere actividades tranquilas.
B2 adjective /ʌnprɪˈpɛrd/

Unprepared

despreparado
Meaning
not ready or able to deal with something
Example
He was unprepared for the difficult exam.
Él estaba desprevenido para el examen difícil.
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.
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.
B1 verb /ʌnˈpæk/

unpack

desempacar
Meaning
to remove items from a container; to explain or analyze something in detail
Example
After arriving home, she began to unpack her suitcase.
Después de llegar a casa, empezó a desempacar su maleta.
B2 adjective /ʌnˈdʒʌst/

Unjust

injusto; incorrecto
Meaning
not fair or right; morally wrong
Example
The punishment was unjust for such a minor offense.
El castigo fue injusto por tal pequeña ofensa.
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.
A2 noun /ˈʌndərweər/

underwear

ropa interior
Meaning
Clothing worn beneath outer clothes, typically next to the skin.
Example
He bought new underwear for the trip.
Compró ropa interior nueva para el viaje.
C2 adjective /ˌʌnsɛrəˈmoʊniəs/

unceremonious

sin ceremonias/rudo
Meaning
Done without formality or courtesy; abrupt or rude.
Example
He made an unceremonious exit from the party.
Él hizo una salida sin ceremonias de la fiesta.
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.
B1 adjective /ʌnˈkʊkt/

uncooked

crudo
Meaning
Not cooked; in a raw state.
Example
Eating uncooked meat can be dangerous.
Comer carne cruda puede ser peligroso.
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.
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.
C1 adjective /ˌjuːnɪˈsɛljʊlər/

unicellular

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

Unused

sin usar; no utilizado
Meaning
not being used; not having been used before
Example
There are many unused rooms in this old mansion.
Hay muchas habitaciones sin usar en esta antigua mansión.
C2 adjective /ˌʌltrəˈmʌndeɪn/

ultramundane

ultramundano
Meaning
Relating to things beyond the physical world; supernatural or transcendental.
Example
Philosophers often discuss ultramundane realities beyond human perception.
Los filósofos a menudo discuten las realidades ultramundanas más allá de la percepción humana.
C1 verb /ʌnˈroʊl/

unroll

desenrollar
Meaning
to open something that is rolled up; to spread out gradually
Example
She unrolled the map on the table to find the route.
Ella desenrolló el mapa sobre la mesa para encontrar la ruta.
B1 adjective /juːˈniːk/

Unique

único; singular; raro
Meaning
being the only one of its kind; unlike anything else
Example
Every snowflake is unique in its pattern.
Cada copo de nieve es único en su patrón.
B2 adjective /ʌnfəˈmɪl.jər/

Unfamiliar

desconocido; extraño
Meaning
not known or recognized; strange
Example
The city was unfamiliar to me since I had never been there before.
La ciudad me era desconocida porque nunca había estado allí antes.
C1 adjective ʌnˈskruːpjʊləs

unscrupulous

deshonesto
Meaning
Having or showing no moral principles; not honest or fair.
Example
Unscrupulous peers can lead adolescents to delinquency.
Los compañeros deshonestos pueden llevar a los adolescentes a la delincuencia.
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.
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.
C2 verb /ʌpˈbreɪd/

upbraid

reprender
Meaning
To scold or criticize someone harshly.
Example
The teacher upbraided the student for being late again.
El maestro reprendió al estudiante por llegar tarde otra vez.
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.
B2 noun ˌɜːbənaɪˈzeɪʃən

urbanization

urbanización
Meaning
The process by which towns and cities are formed and become larger as more people begin living and working in central areas.
Example
Urbanization leads to more developed infrastructure.
La urbanización conduce a una infraestructura más desarrollada.
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.
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.
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.
B2 adjective ʌnˈprɛsɪˌdɛntɪd

unprecedented

sin precedentes
Meaning
Never done or known before; without previous example.
Example
Unprecedented advancements in science changed human lives.
Los avances sin precedentes en la ciencia cambiaron la vida humana.
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.
A1 adjective /ˈjuːs.fəl/

Useful

útil; práctico
Meaning
having a beneficial purpose; practical
Example
This tool is very useful for fixing problems.
Esta herramienta es muy útil para resolver problemas.
C2 noun juːˈbɪkwɪti

ubiquity

ubicuidad
Meaning
The fact of appearing everywhere or of being very common.
Example
The ubiquity of smartphones has transformed communication.
La ubicuidad de los teléfonos inteligentes ha transformado la comunicación.
B2 adjective /ˈʌpˌraɪt/

Upright

honesto y moralmente correcto; vertical o erecto en posición
Meaning
honest and morally correct; vertical or erect in position
Example
She is known for being an upright and honest businesswoman.
Ella es conocida por ser una empresaria honesta y recta.
C2 adjective /ˌʌnpriːpəˈzɛsɪŋ/

unprepossessing

poco atractivo
Meaning
not attractive or appealing in appearance
Example
Despite his unprepossessing looks, he was very kind and intelligent.
A pesar de sus poco atractivos rasgos, era muy amable e inteligente.
B2 adjective /ˌʌndɪˈsaɪdɪd/

Undecided

indeciso; incierto
Meaning
not having made a decision; uncertain
Example
She was undecided about which college to attend.
Ella estaba indecisa sobre qué universidad asistir.
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 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 /ˌʌnəˈteɪnəbl/

unattainable

inalcanzable
Meaning
impossible to achieve, reach, or accomplish
Example
For many, becoming a professional athlete remains an unattainable dream.
Para muchos, convertirse en un atleta profesional sigue siendo un sueño inalcanzable.