Oddity
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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.
B2 adjective /ˌoʊvərˈwɛlmɪŋ/

overwhelming

abrumador
Meaning
Very intense; overpowering.
Example
Large tasks can feel overwhelming.
Las grandes tareas pueden sentirse abrumadoras.
C2 adjective /əbˈstrɛpərəs/

obstreperous

ruidoso y difícil de controlar
Meaning
Noisy and difficult to control.
Example
The obstreperous students disrupted the class.
Los estudiantes ruidosos interrumpieron la clase.
B1 adjective /əˈrɪdʒ.ɪ.nəl/

Original

original; primario; auténtico
Meaning
first; fundamental; primary; authentic
Example
This is the original document, not a copy.
Este es el documento original, no una copia.
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.
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.
B2 noun /ˈɑp.tə.mɪst/

Optimist

optimista
Meaning
a person who tends to be hopeful and confident about the future; someone who sees the good side of things
Example
As an optimist, she always believed things would improve.
Como optimista, siempre creyó que las cosas mejorarían.
C1 adjective /ˈɒptɪməm/

optimum

óptimo
Meaning
Most conducive to a favorable outcome; best.
Example
To achieve optimum results, we need to improve efficiency.
Para lograr los mejores resultados, necesitamos mejorar la eficiencia.
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.
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.
C2 noun /ˈoʊdiəm/

odium

odio
Meaning
general or widespread hatred or disgust directed toward someone as a result of their actions
Example
The scandal brought public odium on the corrupt minister.
El escándalo trajo odio público al ministro corrupto.
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.
B1 verb /ˈɔːrɡənaɪz/

organize

organizar
Meaning
to arrange systematically; to plan and coordinate
Example
She organized a surprise party for her friend.
Ella organizó una fiesta sorpresa para su amiga.
C2 adjective /ˈɔːrəˌtʌnd/

orotund

voz grave y clara
Meaning
full, rich, and clear in sound; pompous in style
Example
The actor's orotund voice filled the theater.
La voz grave del actor llenó el teatro.
C2 noun /ˈɒbsɪkwiːz/

obsequies

ritos fúnebres
Meaning
Funeral rites or ceremonies.
Example
The obsequies for the late leader drew thousands of mourners.
Los ritos fúnebres para el líder fallecido atrajeron a miles de dolientes.
C1 verb /aʊst/

oust

destituir
Meaning
To remove someone from a position or place of power or authority.
Example
The rebels ousted the dictator from power.
Los rebeldes destituyeron al dictador del poder.
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 /əˈpəʊzd/

opposed

opuesto
Meaning
being against or in disagreement with something
Example
She is strongly opposed to animal testing.
Ella está firmemente en contra de las pruebas con animales.
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 /ˈɒfɪʃ/

offish

distante
Meaning
Unfriendly, distant, or reserved in manner.
Example
He seemed offish at the party and avoided most conversations.
Parecía distante en la fiesta y evitaba la mayoría de las conversaciones.
A1 adjective /oʊld/

old

viejo
Meaning
having lived for a long time; not new or young
Example
He still drives his old car.
Él todavía conduce su coche viejo.
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.
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.
B2 adjective /ˈaʊtˌɡoʊɪŋ/

outgoing

sociable
Meaning
Friendly and sociable; inclined to mix with others.
Example
He is an outgoing person who loves meeting new people.
Es una persona sociable a la que le encanta conocer gente nueva.
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.
C2 noun /ˈoʊ.kəm/

oakum

fibra de cuerda vieja
Meaning
loose fibers obtained by untwisting old ropes, used for caulking ships
Example
The shipbuilders used oakum to seal the gaps in the wooden planks.
Los constructores de barcos usaron oakum para sellar las grietas en las tablas de madera.
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.
A2 noun /ˈɒm.lət/

Omelet

tortilla
Meaning
a dish made from beaten eggs cooked in a frying pan and often folded around a filling
Example
She made a cheese omelet for breakfast.
Ella hizo una tortilla de queso para el desayuno.
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.
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.
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.
C2 adjective /ɑːlˈfæktəri/

olfactory

olfatorio
Meaning
Relating to the sense of smell.
Example
The perfume activated her olfactory nerves immediately.
The perfume activated her olfactory nerves immediately.
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.
C2 noun /ˈɒlɪv bɑːb/

Olive barb

barbo oliva
Meaning
A small freshwater fish with olive-colored body and barbels
Example
The olive barb is commonly found in South Asian rivers.
El barbo oliva se encuentra comúnmente en los ríos del sur de Asia.
C1 noun /ˈɒfʃuːt/

offshoot

ramificación
Meaning
A branch or result that develops from something larger or more important.
Example
The startup was an offshoot of a major tech company.
La startup fue una ramificación de una gran empresa de tecnología.
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.
B1 noun /ˈɔr.ə.ʒɪn/

Origin

origen
Meaning
the point or place where something begins, arises, or is derived; the source
Example
Scientists are studying the origin of the universe.
Los científicos están estudiando el origen del universo.
B2 adjective /ˌɑːp.təˈmɪs.tɪk/

optimistic

optimista
Meaning
hopeful and confident about the future
Example
She is optimistic about the success of her new project.
Ella está optimista acerca del éxito de su nuevo proyecto.
C2 adjective /ˈoʊ.vɔɪd/

ovoid

ovoide
Meaning
egg-shaped; resembling an oval or ellipse
Example
The artist painted an ovoid shape in the center of the canvas.
El artista pintó una forma ovoide en el centro del lienzo.
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 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.
C1 adjective /ɔːˈneɪt/

ornate

ornamentado
Meaning
elaborately or highly decorated
Example
The palace hall was filled with ornate furniture and paintings.
El salón del palacio estaba lleno de muebles ornamentados y pinturas.
A1 adjective /ˈɔːr.ɪndʒ/

Orange

naranja
Meaning
having a color between red and yellow like that of a ripe orange fruit
Example
The orange sunset painted the sky magnificently.
El atardecer naranja pintó el cielo magníficamente.
C2 noun /ɔːrˈθɑːɡrəfi/

orthography

ortografía
Meaning
The conventional spelling system of a language.
Example
English orthography can be confusing for learners.
La ortografía del inglés puede ser confusa para los estudiantes.
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.
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 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.
C1 noun /oʊˈeɪ.sɪs/

Oasis

oasis
Meaning
a fertile spot in a desert where water is found; a pleasant refuge
Example
The travelers found an oasis after days in the desert.
Los viajeros encontraron un oasis después de varios días en el desierto.
B1 adverb /əˈrɪdʒɪnəli/

originally

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

oxygen production

producción de oxígeno
Meaning
The process of generating oxygen through photosynthesis or other means.
Example
Plants are vital for oxygen production and the maintenance of life.
Las plantas son vitales para la producción de oxígeno y el mantenimiento de la vida.
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.
B2 noun /ˈaʊt.kʌm/

Outcome

resultado; consecuencia;
Meaning
the result or consequence of an action or situation; the final product
Example
The outcome of the election surprised everyone.
El resultado de las elecciones sorprendió a todos.
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.
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.
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.
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.
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.
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.
A2 noun /ˈʌv.ən/

Oven

horno
Meaning
an enclosed compartment used for heating, baking, or drying food
Example
She baked cookies in the oven for thirty minutes.
Ella horneó galletas en el horno durante treinta minutos.
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.
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.
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.
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.
C2 adjective /ˈɔːrnəri/

ornery

gruñón
Meaning
bad-tempered and combative; stubborn
Example
The ornery old man refused to leave his chair.
El gruñón anciano se negó a dejar su silla.
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.
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 adjective /ˌɔːɡənaɪˈzeɪʃənəl/

organizational

organizacional
Meaning
relating to the structure or arrangement of a company or group
Example
He works on improving the organizational structure of the company.
Él trabaja en mejorar la estructura organizacional de la empresa.
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.
C2 verb /əˈkluːd/

occlude

ocluir
Meaning
To block or close up an opening or passage.
Example
The pipe was occluded by mineral deposits.
La tubería estaba ocluida por depósitos minerales.
C1 noun /əˈpreʃ.ən/

Oppression

opresión; abuso; tiranía;
Meaning
cruel or unjust treatment or exercise of authority; the state of being subject to harsh treatment
Example
The people fought against political oppression.
La gente luchó contra la opresión política.
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.
B2 adjective /ˈɒp.ʃən.əl/

Optional

opcional
Meaning
not compulsory; left to choice
Example
Wearing a tie is optional for this event.
Usar una corbata es opcional para este evento.
C2 adjective /ˈoʊ.kən/

oaken

hecho de roble
Meaning
made of or resembling oak wood
Example
The villagers gathered around the oaken table in the hall.
Los aldeanos se reunieron alrededor de la mesa de roble en el salón.
C2 noun ˈoʊʃən ˌstrætɪfɪˈkeɪʃən

ocean stratification

estratificación oceánica
Meaning
The formation of layers in ocean water due to differences in density.
Example
Ocean stratification affects marine biodiversity.
La estratificación oceánica afecta la biodiversidad marina.
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 /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.
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.
B2 noun/verb /ˈaʊtreɪdʒ/

outrage

indignación
Meaning
A strong feeling of anger and shock; to arouse anger or shock.
Example
The unfair decision caused public outrage.
La decisión injusta causó una indignación pública.
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.
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.
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.
C2 adjective /əbˈsiːkwɪəs/

obsequious

servil
Meaning
Excessively obedient or attentive in a servile way.
Example
The waiter gave an obsequious bow to every customer.
El camarero hizo una reverencia servil a cada cliente.
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 verb /əbˈstrʌkt/

obstruct

obstruir
Meaning
to block or hinder progress; to prevent or impede movement
Example
The fallen tree obstructed the road for several hours.
El árbol caído obstruyó el camino durante varias horas.
A1 interjection /oʊ/

oh

¡Oh!
Meaning
used to express surprise, realization, or understanding
Example
Oh, I didn't know you were here!
¡Oh, no sabía que estabas aquí!
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.
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.
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.
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 /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.
B2 noun /ˈɔɪ.stər/

Oyster

ostra
Meaning
a type of shellfish that can be eaten and sometimes contains pearls
Example
She ordered fresh oysters at the seafood restaurant.
Ella ordenó ostras frescas en el restaurante de mariscos.
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 noun /ɔːˈreɪʃən/

oration

discurso
Meaning
A formal speech, especially one given on a ceremonial occasion
Example
The president delivered an inspiring oration.
El presidente dio un discurso inspirador.
B2 noun /ˈɔːɡənɪzəm/

organism

organismo
Meaning
a living thing that has an organized structure and can grow and reproduce
Example
Every organism needs water to survive.
Todo organismo necesita agua para sobrevivir.
C1 adjective /ˈɔːrθədɑːks/

orthodox

ortodoxo
Meaning
conforming to traditional beliefs or practices
Example
He comes from a very orthodox family.
Él proviene de una familia muy ortodoxa.
C1 adjective /ˈɒptɪk/

optic

óptico
Meaning
Relating to the eye or vision.
Example
The optic nerve carries signals from the eye to the brain.
El nervio óptico lleva señales desde el ojo al cerebro.
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 /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.
C1 adjective /ˌoʊvərˈrɔt/

overwrought

angustiado / excesivamente nervioso
Meaning
extremely agitated or nervous; excessively elaborate
Example
She was too overwrought to speak clearly after the accident.
Ella estaba demasiado angustiada para hablar claramente después del accidente.
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 /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.
C1 noun /ˈoʊ.mən/

Omen

presagio de buena o mala suerte futura
Meaning
an event regarded as a sign of future good or bad luck
Example
Many people consider a black cat crossing your path a bad omen.
Muchas personas consideran que un gato negro cruzando tu camino es un mal presagio.
B2 noun /ˌɑb.zɚˈveɪ.ʃən/

Observation

observación
Meaning
the action of watching something carefully; a comment or remark
Example
The scientist made careful observations of the experiment.
El científico hizo observaciones cuidadosas del experimento.
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.
B2 noun ˈɔː.bɪt

orbit

órbita
Meaning
The curved path of a celestial object around a star, planet, or moon.
Example
The satellite maintains its orbit around Earth.
El satélite mantiene su órbita alrededor de la Tierra.
C1 verb /ˈɒfsɛt/

offset

compensar
Meaning
To counterbalance or compensate for something.
Example
The company's losses were offset by gains in other departments.
Las pérdidas de la compañía fueron compensadas por las ganancias en otros departamentos.
B1 noun /ˌɒp.əˈtjuː.nə.ti/

opportunity

oportunidad
Meaning
A favorable chance or set of circumstances that makes it possible to do something.
Example
She seized the opportunity to study abroad.
Ella aprovechó la oportunidad de estudiar en el extranjero.
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 /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.
B1 noun /ˈɑp.ʃən/

Option

opción
Meaning
a thing that is or may be chosen; an alternative course of action
Example
You have the option to work from home or office.
Tienes la opción de trabajar desde casa o desde la oficina.
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 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 /ˌɑb.lɪˈɡeɪ.ʃən/

Obligation

obligación
Meaning
a duty or commitment; something that must be done legally or morally
Example
Parents have an obligation to care for their children.
Los padres tienen la obligación de cuidar a sus hijos.
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 adjective /ˈɑːsɪˌfaɪd/

ossified

convertido en hueso, rígido
Meaning
Turned into bone or become rigid; unwilling to change.
Example
The company had an ossified management structure that resisted innovation.
La empresa tenía una estructura de gestión rígida que resistía la innovación.
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.
C1 noun /oʊˈmɪʃ.ən/

Omission

omisión; exclusión
Meaning
the action of excluding or leaving out someone or something; a failure to include
Example
The omission of his name from the list was intentional.
La omisión de su nombre de la lista fue intencional.
C2 noun /ˈɒkjʊlɪst/

oculist

optometrista
Meaning
An old-fashioned term for an eye doctor or ophthalmologist.
Example
The village oculist was known for treating various eye diseases.
El oculista del pueblo era conocido por tratar diversas enfermedades oculares.
C1 verb /əˈprɛs/

oppress

oprimir
Meaning
to keep someone down by harsh and unfair use of authority; to suppress
Example
The dictator oppressed the people for decades.
El dictador oprimió a la gente durante décadas.