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A2 adjective/adverb /ˈɒnˌlaɪn/

online

en línea
Meaning
connected to or available through the internet
Example
I prefer shopping online rather than going to stores.
Prefiero comprar en línea en lugar de ir a las tiendas.
C1 adjective /ˈɒm.ɪ.nəs/

Ominous

ominoso; amenazante
Meaning
giving the impression that something bad will happen; threatening; foreboding
Example
The dark clouds looked ominous before the storm.
Las nubes oscuras se veían ominosas antes de la tormenta.
C1 noun /əbˈzɜːrvətɔːri/

observatory

observatorio
Meaning
A building equipped for observing astronomical or meteorological events.
Example
The observatory is open to the public on weekends.
El observatorio está abierto al público los fines de semana.
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.
C1 noun /ˈɔːrdɪnəns/

ordinance

ordenanza
Meaning
An authoritative rule, law, or decree issued by a city, town, or authority.
Example
The city council passed an ordinance banning smoking in public parks.
El consejo municipal aprobó una ordenanza que prohíbe fumar en los parques públicos.
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.
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.
C1 noun /ˈɒn.slɔːt/

onslaught

asalto
Meaning
A fierce or destructive attack.
Example
The village faced an onslaught of enemy forces.
El pueblo enfrentó un asalto de las fuerzas enemigas.
C1 noun /ˈoʊvərˌtoʊn/

overtone

implicación sutil
Meaning
A subtle quality, implication, or additional meaning beyond the obvious.
Example
His speech had political overtones that were hard to ignore.
Su discurso tenía connotaciones políticas que eran difíciles de ignorar.
B1 adjective /ˈɔːɡənaɪzd/

organized

organizado
Meaning
Arranged in a systematic way, especially on a large scale.
Example
An organized approach to work increases productivity and reduces stress.
Un enfoque organizado para el trabajo aumenta la productividad y reduce el estrés.
C2 noun /ˈɒfərtɔːri/

offertory

ofrenda
Meaning
The part of a religious service when offerings are collected; the offering itself.
Example
The offertory was taken during the Sunday service.
La ofrenda fue tomada durante el servicio del domingo.
A1 adjective/adverb /ˈoʊnli/

only

único
Meaning
without others; solely
Example
He is the only person who knows the secret.
Él es la única persona que conoce el secreto.
B1 adverb /əˈrɪdʒɪnəli/

originally

originalmente
Meaning
in the beginning, at first
Example
Originally, she wanted to be a doctor.
Originalmente, ella quería ser doctora.
B2 noun /ˈaʊtbɜːrst/

outburst

explosión repentina de ira o emoción
Meaning
a sudden release of strong emotion or activity
Example
She had an angry outburst during the meeting.
Ella tuvo una explosión de ira durante la reunión.
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.
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.
C1 noun /oʊθ/

Oath

juramento
Meaning
a solemn promise or declaration; a sworn statement
Example
The doctor took an oath to help patients.
El doctor hizo un juramento de ayudar a los pacientes.
B2 noun /ˈɒp.tɪ.mɪ.zəm/

optimism

optimismo
Meaning
Hopefulness and confidence about the future or the successful outcome of something.
Example
Her optimism helped her overcome difficult times.
Su optimismo le ayudó a superar tiempos difíciles.
B2 noun /əbˈsɛʃən/

obsession

obsesión
Meaning
An idea, thought, or concern that continually preoccupies or intrudes on a person's mind.
Example
His obsession with success drove him to work day and night.
Su obsesión con el éxito lo llevó a trabajar día y noche.
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.
C1 verb /ˌoʊvərˈriːtʃ/

overreach

sobreesfuerzo
Meaning
to go beyond what is proper, acceptable, or achievable; to overextend
Example
The politician overreached by making promises he couldn't keep.
El político hizo un esfuerzo excesivo al hacer promesas que no pudo cumplir.
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.
A1 adjective /əʊˈkeɪ/

okay

está bien
Meaning
used to express agreement or acceptance
Example
It's okay to leave early today.
Está bien irse temprano hoy.
C2 noun /ˈoʊɡər/

ogre

ogro
Meaning
A mythical monster, often depicted as large, hideous, and cruel; metaphorically, a cruel or terrifying person.
Example
The villagers feared the ogre who lived in the dark forest.
Los aldeanos temían al ogro que vivía en el bosque oscuro.
C1 verb /ˌaʊtˈstrɛtʃ/

outstretch

extender
Meaning
To extend or stretch something outward.
Example
He outstretched his hand to help her up.
Él extendió su mano para ayudarla a levantarse.
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 adjective ˈɒb.stɪ.nət

obstinate

obstinado
Meaning
Refusing to change one's mind or accept others' advice easily.
Example
He remained obstinate despite the logical arguments.
Él se mantuvo obstinado a pesar de los argumentos lógicos.
C1 noun /ˌɑːk.sɪˈmɔːr.ɒn/

oxymoron

oxímoron
Meaning
a figure of speech where two contradictory terms are combined
Example
The phrase 'deafening silence' is a classic oxymoron.
La frase 'silencio ensordecedor' es un oxímoron clásico.
C2 noun /ˌɒpəˈrɛtə/

operetta

ópera ligera
Meaning
a short opera with light and humorous themes
Example
The theater staged a famous operetta by Gilbert and Sullivan.
El teatro presentó una famosa opereta de Gilbert y Sullivan.
C2 noun /əbˈstɛtrɪks/

obstetrics

obstetricia
Meaning
The branch of medicine dealing with childbirth and care of women giving birth.
Example
She is studying obstetrics to become a specialist in childbirth.
Ella está estudiando obstetricia para convertirse en especialista en partos.
C2 adjective /ˈɒsiəs/

osseous

óseo
Meaning
consisting of or turned into bone; bony
Example
The fossil showed osseous structures of the ancient creature.
El fósil mostró estructuras óseas de la antigua criatura.
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.
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.
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.
C2 verb /ˈɔːreɪt/

orate

orar
Meaning
To speak in a formal, often pompous manner
Example
He began to orate at the ceremony.
Él comenzó a orar en la ceremonia.
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.
C1 noun /ˈɔːrkɪd/

Orchid

órquidea
Meaning
a diverse family of flowering plants known for their exotic and often fragrant flowers
Example
The white orchid on the windowsill bloomed for months.
La orquídea blanca en el alféizar de la ventana floreció durante meses.
C2 noun /ˈaʊtˌrɪɡər/

outrigger

estructura de refuerzo
Meaning
a projecting structure on a boat, used for stability, or a boat fitted with such support
Example
The fisherman paddled his outrigger canoe across the lagoon.
El pescador remó su canoa con outtrigger a través de la laguna.
B1 noun /ˈɔːfɪsər/

officer

oficial
Meaning
a person in a position of authority, especially in law enforcement
Example
The officer gave him a ticket for speeding.
El oficial le dio una multa por exceso de velocidad.
B2 noun /ˈɒfərɪŋ/

offering

oferta
Meaning
something that is given, especially as a gift or contribution
Example
The company’s latest offering is an eco-friendly car.
La última oferta de la empresa es un coche ecológico.
C1 noun /ˈɑd.ɪ.ti/

Oddity

rareza
Meaning
something that is strange or unusual; a peculiar trait
Example
His habit of sleeping standing up was considered an oddity.
Su hábito de dormir de pie se consideraba una rareza.
A2 pronoun /aʊərˈsɛlvz/

ourselves

nosotros mismos
Meaning
used by the speaker to refer to themselves and one or more others as the object of the verb
Example
We should help ourselves before helping others.
Debemos ayudarnos a nosotros mismos antes de ayudar a los demás.
B2 noun /ˈaʊt.laɪn/

Outline

esquema; contorno; resumen
Meaning
a general description or plan showing the essential features of something; the main points
Example
The teacher provided an outline of the course syllabus.
El maestro proporcionó un esquema del syllabus del curso.
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.
B1 adjective /əˈfɪʃəl/

official

oficial
Meaning
relating to or connected with an authority or public office
Example
He is the official spokesperson for the company.
Él es el portavoz oficial de la empresa.
C1 noun /ˈaʊtriːtʃ/

outreach

expansión de la asistencia
Meaning
The act of providing services or support to people who might not otherwise have access to them.
Example
The charity launched a new outreach program for the homeless.
La caridad lanzó un nuevo programa de expansión de la asistencia para las personas sin hogar.
C2 adjective /ˈoʊ.pən ˈhæn.dɪd/

Open-handed

generoso; liberal
Meaning
Generous; liberal; giving freely;
Example
He is very open-handed with his money and always helps those in need.
Él es muy generoso con su dinero y siempre ayuda a los necesitados.
B2 noun /ˈaʊtlʊk/

outlook

perspectiva, pronóstico
Meaning
a person's general attitude or view; a forecast or prospect
Example
The economic outlook for the year is positive.
El pronóstico económico para el año es positivo.
C2 adjective /əˈprəʊ.bri.əs/

opprobrious

despectivo
Meaning
Expressing strong criticism or scorn.
Example
He made opprobrious remarks about his opponent.
Él hizo comentarios despectivos sobre su oponente.
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 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.
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.
C1 adjective /ɒmˈnɪv.ər.əs/

Omnivorous

omnívoro
Meaning
eating both plants and animals; feeding on various kinds of food
Example
Bears are omnivorous animals that eat both plants and meat.
Los osos son animales omnívoros que comen tanto plantas como carne.
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 verb /uːz/

ooze

filtrarse
Meaning
to slowly flow or leak out through small openings or pores
Example
Blood began to ooze from the small cut.
La sangre comenzó a filtrarse de la pequeña herida.
C2 noun /ˈɒksɪdənt/

occident

occidente
Meaning
The countries of the West, especially Europe and America.
Example
The Occident has a long history of philosophical thought.
El occidente tiene una larga historia de pensamiento filosófico.
C1 verb /ˈɔːstrəˌsaɪz/

ostracize

ostracizar
Meaning
to exclude someone from a group or society; to banish or shun
Example
After the scandal, he was ostracized by his former colleagues.
Después del escándalo, fue ostracizado por sus antiguos compañeros de trabajo.
C2 adjective /ˌoʊdəˈrɪfərəs/

odoriferous

fragante
Meaning
having or giving off a smell, especially a strong or pleasant one
Example
The garden was filled with odoriferous flowers.
El jardín estaba lleno de flores fragantes.
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 /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.
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.
B1 verb /əbˈzɜːrv/

observe

observar
Meaning
to watch carefully; to notice or perceive something
Example
Scientists observe the behavior of animals in the wild.
Los científicos observan el comportamiento de los animales en la naturaleza.
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.
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.
A1 verb, adjective /oʊn/

own

poseer
Meaning
to possess something; belonging to oneself
Example
She owns a beautiful house in the city.
Ella posee una hermosa casa en la ciudad.
B1 noun /ˌɑk.jəˈpeɪ.ʃən/

Occupation

ocupación; profesión; toma de control
Meaning
a job or profession; the action of taking control of a place
Example
Teaching is her chosen occupation.
La enseñanza es su ocupación elegida.
C2 verb /ˈɑːskjʊleɪt/

osculate

besar
Meaning
To kiss.
Example
They osculated under the mistletoe during the party.
Ellos se besaron debajo del muérdago durante la fiesta.
A1 preposition, adverb /ˈoʊvər/

over

sobre
Meaning
across, on top of, or beyond
Example
The book is lying over the table.
El libro está sobre la mesa.
C2 noun /ɒmˈnɪʃəns/

omniscience

omnisciencia
Meaning
the state of knowing everything
Example
The novel's narrator has an air of omniscience, revealing every character's thoughts.
El narrador de la novela tiene un aire de omnisciencia, revelando los pensamientos de cada personaje.
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.
C2 noun /oʊˈbleɪʃən/

oblation

oblación
Meaning
a religious offering, especially of bread or wine to God
Example
The priest placed the oblation on the altar during the ceremony.
El sacerdote colocó la oblación en el altar durante la ceremonia.
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.
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.
B2 noun ɔːˈɡæn.ɪk fuːdz

organic foods

alimentos orgánicos
Meaning
Food produced without the use of chemicals such as artificial pesticides, fertilizers, or other artificial agents.
Example
Organic foods are healthier than processed foods.
Los alimentos orgánicos son más saludables que los alimentos procesados.
A1 pronoun /aʊərz/

ours

nuestro
Meaning
belonging to or associated with us
Example
This victory is ours.
Esta victoria es nuestra.
B1 noun /əˈpɪn.jən/

Opinion

opinión
Meaning
a view or judgment formed about something; a belief or assessment based on grounds short of proof
Example
In my opinion, this is the best solution.
En mi opinión, esta es la mejor solución.
C1 noun /ɒpˈtɒmətri/

optometry

optometría
Meaning
The practice or profession of examining the eyes and prescribing corrective lenses.
Example
She studied optometry at the university to become an eye specialist.
Estudió optometría en la universidad para convertirse en especialista en ojos.
C1 noun /ˌəʊvərɪksˌplɔɪˈteɪʃən/

overexploitation

sobreexplotación
Meaning
The unsustainable use of natural resources at a rate that exceeds their ability to regenerate, leading to depletion and environmental degradation.
Example
Overexploitation of natural resources leads to environmental degradation.
La sobreexplotación de los recursos naturales conduce a la degradación ambiental.
B2 adjective ɔːrˈɡæn.ɪk

organic

orgánico
Meaning
Produced or involving production without the use of chemical fertilizers, pesticides, or other artificial agents.
Example
Organic farming improves soil health and reduces pollution.
La agricultura orgánica mejora la salud del suelo y reduce la contaminación.
C2 adjective /ˈɒkjʊlər/

ocular

ocular
Meaning
Relating to the eye or vision.
Example
The patient was referred to a specialist for ocular treatment.
El paciente fue referido a un especialista para tratamiento ocular.
B2 noun, verb /ˈaʊtlɔː/

outlaw

forajido, ilegalizar
Meaning
as a noun: a person who breaks the law and lives outside its protection; as a verb: to make something illegal
Example
The government decided to outlaw the harmful practice.
El gobierno decidió ilegalizar la práctica perjudicial.
C2 adjective /ˌɒbsəˈlɛsnt/

obsolescent

obsoleto
Meaning
Becoming outdated or on the way to becoming obsolete.
Example
The obsolescent technology could not compete with modern devices.
La tecnología obsoleta no pudo competir con los dispositivos modernos.
C2 noun /ˈəʊpəs/

opus

obra creativa
Meaning
A creative work, especially a large and important piece of music or art.
Example
The composer considered the symphony his greatest opus.
El compositor consideró la sinfonía su mayor obra creativa.
B1 noun ˈɒk.sɪ.dʒən

oxygen

oxígeno. Un gas incoloro e inodoro, esencial para la vida.
Meaning
A colorless, odorless reactive gas, the chemical element of atomic number 8 and the life-supporting component of the air.
Example
Oxygen is vital for life.
El oxígeno es vital para la vida.
C1 noun /ˌoʊvərprəˈdʌkʃən/

overproduction

sobreproducción
Meaning
The act of producing more of something than is needed or can be consumed.
Example
The economic crisis was caused by the overproduction of goods.
La crisis económica fue causada por la sobreproducción de bienes.
B2 noun /ɑːks/

Ox

buey
Meaning
a large strong animal used for pulling heavy loads or plowing fields
Example
The farmer used an ox to plow the field.
El agricultor usó un buey para arar el campo.
C2 verb ˈɑːb.fə.skeɪt

obfuscate

ofuscar, oscurecer, confundir
Meaning
Render obscure, unclear, or unintelligible.
Example
Politicians often obfuscate facts to mislead people.
Los políticos a menudo ofuscan los hechos para engañar a la gente.
C1 adjective /ˈɔːrdɪnəl/

ordinal

ordinal
Meaning
Relating to the order or position of something in a sequence (first, second, third, etc.).
Example
The ordinal number 'third' indicates position in a sequence.
El número ordinal 'tercero' indica la posición en una secuencia.
C2 noun /ˌɑːpərˈtuːnɪzəm/

opportunism

oportunismo
Meaning
The practice of taking advantage of opportunities regardless of principles or ethics.
Example
His decision was driven by opportunism, not values.
Su decisión fue impulsada por el oportunismo, no por los valores.
C1 noun /ɒpˈtɒmɪtrɪst/

optometrist

optometrista
Meaning
A healthcare professional who examines eyes and prescribes corrective lenses.
Example
The optometrist prescribed new glasses for her.
El optometrista le recetó nuevos anteojos.
C2 noun /oʊˈbeɪsəns/

obeisance

reverencia
Meaning
A gesture of respect such as a bow or curtsy.
Example
They bowed in obeisance to the king.
Ellos se inclinaron en reverencia al rey.
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.
B2 noun /ˈɒt.ər/

Otter

nutria
Meaning
a mammal with webbed feet that lives near water and feeds on fish
Example
The playful otter swam gracefully in the river.
La nutria juguetona nadaba con gracia en el río.
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 /ˌɒpəˈzɪʃən/

opposition

oposición
Meaning
the action of opposing or resisting something
Example
The opposition to the new law was strong.
La oposición a la nueva ley fue fuerte.
C1 noun /ˌɑːsɪˈleɪʃən/

oscillation

oscilación
Meaning
The movement back and forth at a regular speed.
Example
The oscillation of the pendulum controls the clock.
La oscilación del péndulo controla el reloj.
A2 adjective /ˈɒb.vi.əs/

Obvious

obvio; fácil de entender
Meaning
easily perceived or understood; clear and apparent to the mind
Example
It was obvious that she was upset about something.
Era obvio que ella estaba molesta por algo.
C1 verb /əbˈsɛs/

obsess

obsesionarse
Meaning
To preoccupy or fill the mind of someone continually and to an excessive degree.
Example
She tends to obsess over small details.
Ella tiende a obsesionarse con los pequeños detalles.
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.
B2 adverb /əˈfɪʃəli/

officially

oficialmente
Meaning
in a formal or authorized way
Example
The building was officially opened by the mayor.
El edificio fue oficialmente inaugurado por el alcalde.
C2 noun /ˈoʊ.vər.let/

Overlet

colchón adicional
Meaning
a thin mattress or pad placed over a bed for additional comfort
Example
The overlet makes the bed more comfortable to sleep on.
El overlet hace la cama más cómoda para dormir.
C1 noun /ˈaʊtpoʊst/

outpost

puesto avanzado
Meaning
A small military camp or position at some distance from the main force, used especially as a guard.
Example
The soldiers were stationed at a remote outpost.
Los soldados fueron apostados en un puesto avanzado remoto.
B2 noun /oʊˈbiː.di.əns/

Obedience

obediencia
Meaning
compliance with an order, request, or law; submission to authority
Example
Children should show obedience to their parents.
Los niños deben mostrar obediencia a sus padres.
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 verb /əbˈvɜːrt/

obvert

invertir
Meaning
To turn something so as to face in a different direction; in logic, to convert a proposition by negating both subject and predicate.
Example
The teacher asked the students to obvert the statement for practice.
El maestro pidió a los estudiantes que obvirtieran la declaración para practicar.
A1 adverb /ˈɔːfən/

often

a menudo
Meaning
frequently, many times
Example
I often visit my grandparents on weekends.
A menudo visito a mis abuelos los fines de semana.
C2 noun ˌɒbfəsˈkeɪʃən

obfuscation

ofuscación, confusión
Meaning
The action of making something obscure, unclear, or unintelligible.
Example
The obfuscation of the data made it difficult to interpret.
La ofuscación de los datos dificultó su interpretación.
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.
C1 noun ˌoʊ.vɚˈɡreɪ.zɪŋ

overgrazing

sobrepastoreo
Meaning
The practice of allowing livestock to graze to the point of damaging vegetation.
Example
Overgrazing leads to soil erosion and loss of biodiversity.
El sobrepastoreo lleva a la erosión del suelo y la pérdida de biodiversidad.
A1 pronoun /aʊər/

our

nuestro
Meaning
belonging to or associated with the speaker and one or more other people
Example
This is our house.
Esta es nuestra casa.
B2 noun /əbˈdʒek.ʃən/

Objection

objeción; desacuerdo; protesta;
Meaning
an expression of disagreement or disapproval; a reason for disagreeing
Example
The lawyer raised an objection during the trial.
El abogado levantó una objeción durante el juicio.
C2 noun /ˈɒn.rʌʃ/

onrush

embestida
Meaning
A sudden powerful forward or downward rush or flow.
Example
The onrush of water swept away the bridge.
La embestida de agua arrastró el puente.
C2 adjective /ˌoʊvərˈwiːnɪŋ/

overweening

excesivamente arrogante
Meaning
excessively arrogant or prideful
Example
His overweening pride cost him many friends.
Su exceso de orgullo le costó muchos amigos.
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.
B2 noun oʊˈbiː.sə.t̬i

obesity

obesidad
Meaning
The condition of being grossly fat or overweight.
Example
Obesity increases the risk of diabetes and heart disease.
La obesidad aumenta el riesgo de diabetes y enfermedades cardíacas.
C2 noun /ˈɔː.rɪ.fɪs/

orifice

orificio
Meaning
an opening or hole, especially in the body or a device
Example
The medicine was applied through a small orifice in the device.
El medicamento se aplicó a través de un pequeño orificio en el dispositivo.
C2 noun /ɑːlˈfækʃən/

olfaction

olfato
Meaning
The sense of smell; the process of detecting and perceiving odors.
Example
Dogs have a highly developed sense of olfaction.
Los perros tienen un sentido del olfato muy desarrollado.
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.
C2 verb /ˈɑːblɪˌɡeɪt/

obligate

obligar
Meaning
to bind legally or morally; to compel someone to do something
Example
The contract obligates the company to provide timely service.
El contrato obliga a la empresa a proporcionar un servicio puntual.
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 /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.