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C1 adjective ˈɒptɪmaɪzd

optimized

optimizados, mejorado, más eficiente
Meaning
Made as fully perfect, functional, or effective as possible; improved to achieve maximum efficiency.
Example
The system has been optimized for faster performance.
El sistema ha sido optimizado para un rendimiento más rápido.
C2 noun /ˈɒrɪz(ə)n/

orison

oración
Meaning
a prayer, especially a devout or formal one
Example
He whispered a quiet orison before going to sleep.
Susurró una oración tranquila antes de dormir.
C1 noun /əbˈstrʌkʃən/

obstruction

obstáculo
Meaning
Something that blocks or gets in the way; the action of obstructing.
Example
There was an obstruction on the railway track.
Había un obstáculo en la vía del tren.
B2 verb /əˈfend/

offend

ofender
Meaning
to cause displeasure or resentment; to hurt someone's feelings
Example
His rude comments offended many people at the meeting.
Sus comentarios groseros ofendieron a muchas personas en la reunión.
B2 noun /oʊk/

oak

roble
Meaning
a large tree that produces acorns and has strong, hard wood
Example
The old oak tree provided shade for the entire yard.
El viejo roble dio sombra a todo el jardín.
C2 noun (plural) /ˈɔːrdʒiːz/

orgies

orgías
Meaning
Wild gatherings involving excessive indulgence in food, drink, or sexual activity.
Example
The ancient Romans were infamous for their lavish feasts and orgies.
Los antiguos romanos eran infames por sus banquetes lujosos y orgías.
B2 adverb /ˌoʊvərˈnaɪt/

Overnight

de la noche a la mañana; de repente; muy rápidamente
Meaning
during the night; suddenly; very quickly
Example
The city was transformed overnight.
La ciudad fue transformada de la noche a la mañana.
C2 noun /ˌɒn.əˌmæt.əˈpiː.ə/

onomatopoeia

onomatopeya
Meaning
The formation of a word from a sound associated with what is named.
Example
The word 'buzz' is an example of onomatopoeia.
La palabra 'zumbido' es un ejemplo de onomatopeya.
C1 adverb /ˈaʊtwədli/

Outwardly

externamente; superficialmente;
Meaning
on the surface; externally; in appearance
Example
Outwardly, he seemed calm, but inside he was nervous.
Exteriormente, parecía tranquilo, pero por dentro estaba nervioso.
B2 adjective /ˈɔː.də.li/

Orderly

ordenado; sistemático; pacífico
Meaning
well-organized; systematic; peaceful
Example
Please keep your desk orderly and clean.
Por favor, mantén tu escritorio ordenado y limpio.
B2 noun /ˈɔːrɡənaɪzər/

organizer

organizador
Meaning
a person who arranges or coordinates activities, events, or groups; a tool or item used to keep things in order
Example
She worked as the main organizer of the international conference.
Ella fue la principal organizadora de la conferencia internacional.
B2 adjective /aʊtˈstændɪŋ/

outstanding

extraordinario
Meaning
extremely good or impressive; not yet resolved or paid
Example
She received an award for her outstanding performance.
Recibió un premio por su actuación extraordinaria.
C2 adjective /ɒmˈnɪʃ.ənt/

Omniscient

omnisciente
Meaning
having complete knowledge; all-knowing
Example
The narrator in the novel appears to be omniscient, knowing every character's thoughts.
El narrador en la novela parece ser omnisciente, conociendo todos los pensamientos de los personajes.
C1 noun /ˈɔːr.ə.tɔːr.i/

oratory

oratoria
Meaning
The art of public speaking; skilled and confident delivery of speeches to an audience.
Example
His exceptional oratory skills won him the debate competition.
Sus excepcionales habilidades oratorias le ganaron la competencia de debate.
B1 adjective /ˌoʊld ˈfæʃənd/

old-fashioned

anticuado
Meaning
not modern; belonging to an earlier time
Example
He still wears an old-fashioned hat.
Él todavía usa un sombrero anticuado.
C1 adverb /ˈɒp.tɪ.məl.i/

optimally

de manera óptima
Meaning
In the most effective or efficient way possible.
Example
Tasks should be allocated optimally for maximum output.
Las tareas deben asignarse de manera óptima para obtener el máximo rendimiento.
A2 noun /ˈɒf.ɪs/

office

oficina
Meaning
a room or building where people work, usually at desks
Example
She left the office early to attend a family event.
Ella dejó la oficina temprano para asistir a un evento familiar.
B2 noun /ˈɒpəreɪtər/

operator

operador
Meaning
a person who operates equipment, a business, or controls something
Example
The machine operator ensured that everything ran smoothly.
El operador de la máquina se aseguró de que todo funcionara sin problemas.
C1 adjective ˈɒk.sɪ.də.tɪv

oxidative

Relacionado con la oxidación
Meaning
Related to or caused by oxidation, especially cellular damage from free radicals.
Example
Excess stress can lead to oxidative damage in cells.
El estrés excesivo puede causar daño oxidativo en las células.
A2 verb /oʊˈbeɪ/

obey

obedecer
Meaning
to follow orders or instructions; to comply with rules
Example
Children should obey their parents and teachers.
Los niños deben obedecer a sus padres y maestros.
C1 adjective /ˈɒptɪkəl/

optical

óptico
Meaning
related to or used in seeing or sight
Example
The optical illusion fooled everyone at the exhibition.
La ilusión óptica engañó a todos en la exposición.
C1 adjective /əˈprɛs.ɪv/

Oppressive

opresivo
Meaning
Harsh and authoritarian; overwhelming; causing distress; tyrannical;
Example
The oppressive heat made it difficult to work outside during the summer.
El calor opresivo dificultaba trabajar afuera durante el verano.
B1 verb /əˈkɜːr/

occur

ocurrir
Meaning
to happen or take place; to be found or present
Example
The accident occurred at the intersection during rush hour.
El accidente ocurrió en la intersección durante la hora punta.
B2 noun /ˈaʊt.breɪk/

Out-break

brote
Meaning
a sudden occurrence or eruption of something, especially disease or violence
Example
The outbreak of flu affected many students in the school.
El brote de gripe afectó a muchos estudiantes en la escuela.
B2 noun ˈaʊt.pʊt

output

producción
Meaning
The amount of something produced by a person, machine, or industry.
Example
Climate change reduces agricultural output.
El cambio climático reduce la producción agrícola.
C1 noun ˈaʊt.sɔːr.sɪŋ

outsourcing

externalización
Meaning
The practice of having certain job functions done outside a company instead of having an in-house department or employee handle them.
Example
Many companies use outsourcing to reduce labor costs.
Muchas empresas utilizan la externalización para reducir los costos laborales.
C1 adjective /əˈblɪɡ.ə.tɔː.ri/

obligatory

obligatorio
Meaning
Required by a legal, moral, or other rule; compulsory.
Example
Wearing a seatbelt is obligatory in most countries.
Usar el cinturón de seguridad es obligatorio en la mayoría de los países.
B2 noun /ˈaʊtˌfɪt/

outfit

conjunto de ropa
Meaning
A set of clothes worn together, often for a particular occasion.
Example
She wore a beautiful outfit to the party.
Ella usó un hermoso conjunto de ropa para la fiesta.
C1 verb /ˌaʊtˈstrɪp/

outstrip

superar
Meaning
To go faster or do better than someone or something; to surpass.
Example
The company outstripped its competitors in sales last year.
La compañía superó a sus competidores en ventas el año pasado.
C1 noun /oʊˈveɪʃən/

ovation

ovación
Meaning
an enthusiastic show of approval, especially by clapping hands
Example
The actor received a standing ovation after his performance.
El actor recibió una ovación de pie después de su actuación.
B2 noun /ˈɔr.fən/

Orphan

huérfano
Meaning
a child whose parents are dead; someone without protective support
Example
The orphan was adopted by a loving family.
El huérfano fue adoptado por una familia amorosa.
A2 noun /ˈɒbdʒɪkt/

object

objeto
Meaning
a thing that can be seen and touched
Example
The table is an object in the room.
La mesa es un objeto en la habitación.
B1 adjective /əˈbiː.di.ənt/

Obedient

obediente
Meaning
willing to comply with orders or instructions; submissive
Example
The obedient student always follows the teacher's instructions.
El estudiante obediente siempre sigue las instrucciones del profesor.
B1 adverb /əˈkeɪʒənəli/

Occasionally

ocasionalmente; de vez en cuando;
Meaning
sometimes; from time to time; not regularly
Example
I occasionally visit my grandmother on weekends.
A veces visito a mi abuela los fines de semana.
B2 adjective /əˈfen.sɪv/

Offensive

ofensivo; insultante; agresivo
Meaning
causing displeasure or resentment; insulting; aggressive
Example
His offensive remarks hurt everyone's feelings.
Sus comentarios ofensivos lastimaron los sentimientos de todos.
C1 adjective /ˌɔːrnəˈmɛntl/

ornamental

ornamental
Meaning
Serving as decoration; decorative rather than functional.
Example
The garden was filled with ornamental plants.
El jardín estaba lleno de plantas ornamentales.
C2 noun /əbˈsɪdiən/

obsidian

obsidiana (roca volcánica oscura y vidriosa)
Meaning
A hard, dark, glasslike volcanic rock formed by rapid solidification of lava.
Example
The knife was made from sharp obsidian.
El cuchillo estaba hecho de obsidiana afilada.
B2 noun /ˈoʊvərpæs/

overpass

paso elevado
Meaning
A bridge that carries one road or railway over another.
Example
The new overpass reduced traffic congestion in the city.
El nuevo paso elevado redujo la congestión de tráfico en la ciudad.
C1 adjective /ˈɑp.ər.ə.tɪv/

Operative

activo; en efecto; funcionando; operativo;
Meaning
Functioning; in effect; working; active;
Example
The new safety protocols became operative immediately after the accident.
Los nuevos protocolos de seguridad se volvieron operativos inmediatamente después del accidente.
C1 noun /ˈɔr.ə.kəl/

Oracle

oráculo
Meaning
a person regarded as a source of wise counsel; in ancient times, a priest or priestess acting as a medium
Example
The ancient Greeks consulted the oracle at Delphi.
Los antiguos griegos consultaban el oráculo en Delfos.
C1 adjective/adverb /ˌɒfˈhænd/

offhand

sin pensar
Meaning
Without previous thought or preparation; casual and sometimes dismissive.
Example
She gave an offhand reply to his serious question.
Ella dio una respuesta sin pensarlo a su seria pregunta.
B2 adjective /aʊtˈreɪdʒəs/

outrageous

atroz
Meaning
Shockingly bad or excessive; very unusual or amusing.
Example
The comedian told an outrageous joke.
El comediante contó un chiste atroz.
C1 adjective /aʊtˈmoʊdɪd/

outmoded

desfasado
Meaning
No longer in fashion or useful; outdated.
Example
That old computer is completely outmoded.
Esa computadora antigua está completamente desfasada.
C1 verb /ˈɒs.ɪ.leɪt/

oscillate

moverse o balancearse de un lado a otro entre dos puntos o estados
Meaning
To swing or move back and forth between two points or states
Example
The stock market tends to oscillate during uncertain times.
El mercado de valores tiende a oscilar durante tiempos inciertos.
B1 verb অকার্স

occurs

sucede
Meaning
Happens or takes place, especially as a result of something.
Example
Snowfall occurs in regions with freezing temperatures.
La nieve ocurre en regiones con temperaturas bajo cero.
C1 noun ˌɒk.sɪˈdeɪ.ʃən

oxidation

oxidación
Meaning
A chemical reaction that involves the combination of a substance with oxygen, often causing deterioration.
Example
Oxidation causes metal surfaces to weaken.
La oxidación debilita las superficies metálicas.
B2 noun /ˈaʊtˌskɜːrt/

outskirt

las afueras de la ciudad
Meaning
the outer edge or border of a town or city
Example
They built a new factory on the outskirts of the city.
Construyeron una nueva fábrica en las afueras de la ciudad.
C2 noun /ˌɒstɛnˈteɪʃən/

ostentation

ostentación
Meaning
excessive display of wealth or knowledge intended to attract admiration or envy
Example
The billionaire’s party was full of ostentation and luxury.
La fiesta del multimillonario estaba llena de ostentación y lujo.
C2 adjective /ˈɒf.biːt/

offbeat

inusual
Meaning
Unusual, unconventional, or different from the norm.
Example
She has a very offbeat sense of humor.
Ella tiene un sentido del humor muy inusual.
C1 verb /ɔːrˈdeɪn/

ordain

ordenar
Meaning
To officially make someone a priest or minister; to decree or order something officially.
Example
The bishop will ordain three new priests this Sunday.
El obispo ordenará tres nuevos sacerdotes este domingo.
A1 adverb /ɔːf/

off

apagado
Meaning
away from a place, position, or time; not functioning
Example
He turned off the light before leaving the room.
Apagó la luz antes de salir de la habitación.
C2 noun /ˈɒb.stɪ.nə.si/

obstinacy

obstinación
Meaning
Stubborn refusal to change one's opinion or chosen course of action, despite attempts to persuade one to do so.
Example
His obstinacy made negotiations difficult.
Su obstinación hizo que las negociaciones fueran difíciles.
A2 adjective /ɒd/

Odd

extraño; inusual; diferente de lo que es normal o esperado
Meaning
strange; unusual; different from what is normal or expected
Example
That's an odd way to solve the problem.
Esa es una forma extraña de resolver el problema.
C1 noun /əbˈzɜːvəns/

observance

observancia
Meaning
The practice of following a custom, rule, or religious law.
Example
The festival is held in observance of a centuries-old tradition.
El festival se celebra en observancia de una tradición centenaria.
C2 noun /əˈblɪkwɪti/

obliquity

oblicuidad
Meaning
Deviation from moral or usual conduct; indirectness or lack of straightforwardness.
Example
The politician was criticized for the obliquity of his answers.
El político fue criticado por la oblicuidad de sus respuestas.
C2 adjective /ɒmˈnɪp.ə.tənt/

omnipotent

omnipotente
Meaning
Having unlimited power; able to do anything; all-powerful.
Example
In many religions, God is considered omnipotent.
En muchas religiones, Dios se considera omnipotente.
C1 adjective əʊˈpeɪk

opaque

opaco, impenetrable, difícil de entender
Meaning
Not able to be seen through; not transparent; difficult to understand.
Example
The glass was too opaque to see through.
El vidrio era tan opaco que no se podía ver a través de él.
C1 adjective /ˌɒstɛnˈteɪʃəs/

ostentatious

ostentoso
Meaning
Characterized by a showy or pretentious display intended to impress others.
Example
He wore an ostentatious gold chain to the party.
Llevaba una cadena de oro ostentosa en la fiesta.
C2 verb /oʊˈpaɪn/

opine

expresar una opinión
Meaning
to express an opinion or belief
Example
The professor opined that the policy would fail.
El profesor opinó que la política fracasaría.
C2 verb /ˈɑːbdʒərˌɡeɪt/

objurgate

reprender severamente
Meaning
to scold or rebuke severely
Example
The teacher objurgated the student for being dishonest.
El maestro reprendió severamente al estudiante por ser deshonesto.
C1 noun /ˈoʊvərˌtʊr/

overture

overture / propuesta
Meaning
An introduction to something more substantial; a proposal or preliminary action.
Example
The peace overture was welcomed by both nations.
La propuesta de paz fue bienvenida por ambas naciones.
B2 noun /ˈoʊ.dər/

Odour

olor
Meaning
a distinctive smell, especially an unpleasant one
Example
The odour of fresh bread filled the kitchen.
El olor de pan fresco llenó la cocina.
C2 adjective /ˈɑːbdjʊrət/

obdurate

obstinado
Meaning
Stubbornly refusing to change one's opinion or course of action.
Example
He remained obdurate despite everyone's pleas.
Él permaneció obstinado a pesar de las súplicas de todos.
C2 adjective /ɒˈstɛnsɪv/

ostensive

ostensible
Meaning
clearly demonstrative or pointing out; explicitly shown
Example
The teacher gave an ostensive example to clarify the concept.
La maestra dio un ejemplo ostensible para aclarar el concepto.
B2 noun /əˌrɪʒ.əˈnæl.ə.ti/

Originality

originalidad
Meaning
the quality of being novel or unusual; the ability to think independently and creatively
Example
The artist's work showed great originality and creativity.
La obra del artista mostró gran originalidad y creatividad.
C2 verb /ˌoʊvərˈliːp/

overleap

saltar por encima
Meaning
To jump over something; to omit or disregard something.
Example
He managed to overleap the fence easily.
Él logró saltar la cerca fácilmente.
B2 noun /ɒpˈtɪʃən/

optician

optometrista
Meaning
A person who makes or sells glasses and contact lenses.
Example
The optician adjusted my new glasses to fit better.
El optometrista ajustó mis nuevas gafas para que quedaran mejor.
B1 noun /ˈɒbstəkəlz/

obstacles

obstáculos
Meaning
Things that block one's way or prevent or hinder progress.
Example
Obstacles in life can often lead to valuable lessons.
Los obstáculos en la vida a menudo conducen a lecciones valiosas.
B1 adjective /ˌoʊvərˈweɪt/

overweight

sobrepeso
Meaning
heavier than is considered healthy or normal
Example
The doctor advised him to lose weight as he was overweight.
El doctor le aconsejó perder peso ya que tenía sobrepeso.
C1 noun /oʊˈbɪt.ʃu.er.i/

Obituary

obituario
Meaning
a notice of someone's death published in a newspaper; biographical account of deceased person
Example
The newspaper published his obituary yesterday.
El periódico publicó su obituario ayer.
C1 adjective /oʊˈvɜːrt/

overt

abierto
Meaning
Done or shown openly; not hidden or secret.
Example
There was an overt display of hostility between the rivals.
Hubo una exhibición abierta de hostilidad entre los rivales.
C1 noun /ˌɒbstəˈtrɪʃən/

obstetrician

obstetra
Meaning
A doctor specializing in pregnancy, childbirth, and women's reproductive health.
Example
The obstetrician monitored the mother’s health throughout the pregnancy.
El obstetra monitoreó la salud de la madre durante el embarazo.
A1 verb /ˈoʊpən/

open

abrir
Meaning
to move something so as to allow access; to begin
Example
Please open the door for me.
por favor abre la puerta para mí.
C1 noun /ˈoʊ.vər spɪl/

Over-spill

desbordamiento
Meaning
the overflow of liquid from a container; excess that cannot be contained
Example
The overspill from the river flooded nearby farms.
El desbordamiento del río inundó las granjas cercanas.
C1 verb /ˌoʊvərˈrʌn/

overrun

invadir
Meaning
to spread over or occupy completely; to exceed a limit or time
Example
The garden was overrun with weeds.
El jardín estaba invadido de maleza.
C2 verb /ˈɒsɪfaɪ/

ossify

osificar
Meaning
to turn into bone or become rigid and inflexible
Example
With age, some tissues tend to ossify.
Con la edad, algunos tejidos tienden a osificarse.
B1 noun /əˈkeɪ.ʒən/

Occasion

ocasión; evento especial
Meaning
a particular time or instance of an event; a special celebration
Example
Their wedding was a joyous occasion.
Su boda fue una ocasión alegre.
B2 noun /əˈfɛns/

offense

delito
Meaning
an illegal act; a crime
Example
The offense was committed in broad daylight.
El delito fue cometido a plena luz del día.
A2 preposition /ˈɒntu/

onto

sobre
Meaning
moving to a position on the surface of something
Example
She jumped onto the table to get the book.
Ella saltó sobre la mesa para coger el libro.
B1 noun /aʊl/

Owl

búho
Meaning
a nocturnal bird of prey with large eyes and a hooked beak
Example
The owl hooted softly in the darkness of the forest.
El búho hooteó suavemente en la oscuridad del bosque.
B2 noun /ɔːrˈɡæn.ɪk ˈfɑːr.mɪŋ/

organic farming

agricultura orgánica
Meaning
Farming method that avoids synthetic chemicals and fertilizers, using natural methods instead.
Example
Organic farming improves soil health and reduces pollution.
La agricultura orgánica mejora la salud del suelo y reduce la contaminación.
C2 adjective /əbˈtruːsɪv/

obtrusive

obtrusivo
Meaning
noticeable in an unpleasant or unwelcome way; intrusive
Example
The advertisement was so obtrusive that it ruined the user’s experience.
El anuncio era tan obtrusivo que arruinó la experiencia del usuario.
C2 noun /ˈɑb.lə.kwi/

Obloquy

crítica severa o abuso verbal; condena pública
Meaning
harsh criticism or verbal abuse; strong public condemnation
Example
The politician faced obloquy after the scandal.
El político enfrentó obloquio después del escándalo.
B2 verb /əˈpoʊz/

oppose

oponerse
Meaning
to disagree with or resist; to act against
Example
Many citizens oppose the new tax policy.
Muchos ciudadanos se oponen a la nueva política fiscal.
C1 verb /ˌoʊvərˈʃædoʊ/

overshadow

opacar
Meaning
to appear more important or significant than something else, reducing its impact
Example
The scandal overshadowed his achievements.
El escándalo opacó sus logros.
C1 noun /ˈɑn.set/

Onset

inicio; comienzo
Meaning
the beginning or early stages of something; the start of a medical condition
Example
The onset of winter brought heavy snowfall.
El inicio del invierno trajo fuertes nevadas.
B1 adjective /ˌoʊvərˈsiːz/

overseas

en el extranjero
Meaning
in or to a foreign country across the sea
Example
He went overseas for higher education.
Él fue al extranjero para estudiar.
B1 noun ˌɔː.ɡən.aɪˈzeɪ.ʃən

organization

organización
Meaning
An organized group of people with a particular purpose, such as a business or government department.
Example
The organization was officially inaugurated in 2024.
La organización fue inaugurada oficialmente en 2024.
C2 noun /əbˈstrʌkʃənɪst/

obstructionist

obstruccionista
Meaning
a person who deliberately delays or prevents progress by being uncooperative or oppositional
Example
The obstructionist in the committee kept delaying the decision-making process.
El obstruccionista en el comité siguió retrasando el proceso de toma de decisiones.
B1 noun /ˈɑb.stə.kəl/

Obstacle

obstáculo
Meaning
something that blocks or makes progress difficult; a barrier
Example
Bad weather was the main obstacle to our journey.
El mal tiempo fue el principal obstáculo para nuestro viaje.
C2 noun /ˌɔːrəˈtɔːri.oʊ/

oratorio

composición musical religiosa
Meaning
A large-scale musical composition for orchestra, choir, and soloists, usually on a sacred theme, performed without costumes or scenery.
Example
Handel's 'Messiah' is one of the most famous oratorios ever written.
El 'Mesías' de Handel es uno de los oratorios más famosos jamás escritos.
C1 verb /ˌoʊvərˈruːl/

overrule

anular
Meaning
to reject or disallow by exercising one's superior authority; to override a decision
Example
The judge overruled the objection from the defense attorney.
El juez anuló la objeción del abogado defensor.
B2 noun /əbˈzɜːvər/

observer

observador
Meaning
a person who watches or notices something
Example
The observer took notes during the meeting.
El observador tomó notas durante la reunión.
C1 noun /ˈɒf.sprɪŋ/

offspring

descendencia
Meaning
a person's child or children; an animal's young
Example
The bird carefully fed its offspring.
El pájaro alimentó cuidadosamente a su descendencia.
A1 preposition /ɒn/

on

sobre
Meaning
physically in contact with and supported by a surface
Example
The book is on the table.
El libro está sobre la mesa.
C2 noun ˈɒpjʊləns

opulence

opulencia
Meaning
Great wealth or luxuriousness.
Example
The opulence of the mansion was evident in its ornate furnishings.
La opulencia de la mansión era evidente en sus muebles ornamentados.
B1 noun ˌɒpəˈtjuːnɪtiz

opportunities

oportunidades
Meaning
A set of circumstances that makes it possible to do something; chances for advancement or success.
Example
Opportunities for jobs decreased.
Las oportunidades para trabajos disminuyeron.
A1 noun/adjective/adverb /ˌaʊtˈsaɪd/

outside

afuera
Meaning
the external part or surface of something; beyond the boundary
Example
Children were playing outside in the yard.
Los niños estaban jugando afuera en el jardín.
C2 noun /ˈoʊvərlɔːrd/

overlord

señor
Meaning
A ruler, master, or person of great power and authority over others.
Example
The peasants were forced to pay taxes to their overlord.
Los campesinos fueron obligados a pagar impuestos a su señor.
C2 adjective /ˌɔːfˈkiː/

off-key

desafinado
Meaning
out of tune; not in accordance with expected standards
Example
The singer was slightly off-key during the performance.
El cantante estaba ligeramente desafinado durante la actuación.
C2 noun /ˈɑːbəlɪsk/

obelisk

obelisco
Meaning
A tall, four-sided, narrow tapering monument with a pyramid-shaped top.
Example
The ancient Egyptians built obelisks to honor their gods.
Los antiguos egipcios construyeron obeliscos para honrar a sus dioses.
C2 noun /oʊf/

Oaf

una persona torpe, estúpida o insensible
Meaning
a clumsy, stupid, or insensitive person
Example
Don't be such an oaf - handle the dishes carefully!
¡No seas un oaf así - maneja los platos con cuidado!
C2 noun /ˌɒktədʒəˈnɛəriən/

octogenarian

octogenario
Meaning
A person who is between 80 and 89 years old.
Example
The octogenarian still jogs every morning to stay healthy.
El octogenario aún corre todas las mañanas para mantenerse saludable.
C1 noun /ˈɔɪntmənt/

ointment

ungüento
Meaning
A smooth, oily substance applied to the skin for healing or soothing.
Example
The doctor prescribed an ointment for the burn on his arm.
El doctor recetó un ungüento para la quemadura en su brazo.
C1 noun /ˌɒk.sɪ.dʒɪˈneɪ.ʃən/

oxygenation

suministro o tratamiento con oxígeno
Meaning
The process of supplying or treating with oxygen.
Example
Deep breathing exercises improve oxygenation of the body.
Los ejercicios de respiración profunda mejoran el suministro de oxígeno en el cuerpo.
C1 verb /ˈoʊvərˌhɔːl/

overhaul

revisión completa
Meaning
to examine thoroughly and repair or improve something that is worn or ineffective
Example
The company decided to overhaul its outdated computer system.
La compañía decidió hacer una revisión completa a su sistema de computadoras obsoleto.
C1 noun /əˈfen.dər/

Offender

delincuente; infractor de la ley
Meaning
a person who commits an illegal act; someone who breaks the law
Example
The young offender was sentenced to community service.
El joven delincuente fue sentenciado a servicio comunitario.
C1 adjective /ˌaʊtˈspoʊkən/

Outspoken

franco
Meaning
frank; speaking directly
Example
She is known for being outspoken about social issues.
Es conocida por ser franca sobre los problemas sociales.
B2 verb /oʊˈmɪt/

omit

omitir
Meaning
to leave out or exclude; to fail to include something
Example
Please don't omit any important details from your report.
Por favor, no omitas detalles importantes de tu informe.
B2 noun /wʌn θɜːd/

one-third

un tercio
Meaning
one part of something that is divided into three equal parts
Example
One-third of the class was absent today.
Un tercio de la clase estaba ausente hoy.
C2 verb /aʊtˈraɪd/

outride

adelantar
Meaning
to ride faster, farther, or better than someone else
Example
The young rider managed to outride his competitors in the race.
El joven jinete logró adelantar a sus competidores en la carrera.
A1 adverb /wʌns/

Once

una vez; alguna vez en el pasado
Meaning
one time only; at some time in the past; formerly
Example
I have been to Paris once in my life.
He estado en París una vez en mi vida.
C1 adjective /əˈblaɪdʒɪŋ/

obliging

servicial
Meaning
Willing to help or do favors; accommodating.
Example
The staff at the hotel were very obliging and friendly.
El personal del hotel era muy servicial y amable.
C1 verb /aʊtˈlɪv/

outlive

sobrevivir
Meaning
to live longer than someone or something else
Example
She outlived all her siblings.
Ella vivió más tiempo que todos sus hermanos.
B2 verb /ɒpt/

opt

elegir
Meaning
to choose or decide to do something instead of something else
Example
Many students opt to study abroad for better opportunities.
Muchos estudiantes optan por estudiar en el extranjero para tener mejores oportunidades.
B2 noun /ˈaʊtɪŋ/

outing

excursión
Meaning
a short trip or excursion, often for leisure or enjoyment
Example
They had a lovely outing at the beach last weekend.
Tuvieron una maravillosa excursión en la playa el fin de semana pasado.
C1 adjective /oʊˈbiːs/

obese

obeso
Meaning
Extremely overweight; having an excessive amount of body fat.
Example
The doctor advised the obese patient to adopt a healthier lifestyle.
El doctor le recomendó al paciente obeso adoptar un estilo de vida más saludable.
C1 noun /ˈɑːlɪˌɡɑːrki/

oligarchy

oligarquía
Meaning
A small group of people having control of a country, organization, or institution.
Example
The nation was ruled by a wealthy oligarchy that controlled all resources.
La nación fue gobernada por una oligarquía rica que controlaba todos los recursos.
C1 adjective /ˌaʊt ən ˈaʊt/

out-and-out

completo
Meaning
complete; absolute; used to emphasize something extreme
Example
The speech was an out-and-out lie.
El discurso fue una mentira completa.
C1 verb əˈblɪt.ə.reɪt

obliterate

destruir
Meaning
To destroy utterly; wipe out completely, to erase or remove something completely.
Example
The storm obliterated entire villages.
La tormenta destruyó aldeas enteras.
C1 noun /əˈkɜr.əns/

Occurrence

suceso
Meaning
an instance or event of something happening; the fact of occurring
Example
The occurrence of earthquakes is common in this region.
La ocurrencia de terremotos es común en esta región.