organism
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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 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.
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.
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 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.
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.
B2 adjective /ˈɒp.tɪ.məl/

optimal

óptimo, más favorable
Meaning
Best or most favorable; the most effective under particular conditions.
Example
The optimal temperature for plant growth is around 25°C.
La temperatura óptima para el crecimiento de las plantas es de alrededor de 25°C.
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No longer in fashion or useful; outdated.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.
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.
C1 verb /ˌoʊvərˈpaʊər/

overpower

dominar
Meaning
To defeat or gain control over someone or something by using greater strength or force.
Example
The soldiers managed to overpower the enemy forces.
Los soldados lograron dominar las fuerzas enemigas.
B2 noun ˈəʊnəʃɪp

ownership

propiedad
Meaning
The act, state, or right of possessing something; legal title to something.
Example
Ownership of resources was crucial.
La propiedad de los recursos fue crucial.
B2 verb /ˌoʊvərˈloʊd/

overload

sobrecargar
Meaning
to load with too much weight or cargo; to give too much work or information
Example
Don't overload the washing machine or it might break down.
No sobrecargues la lavadora o podría romperse.
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.
A2 adjective /ˈɑp.ə.zɪt/

Opposite

opuesto; completamente diferente; cara a cara; inverso;
Meaning
Contrary; completely different; facing each other; reverse;
Example
They have opposite views on politics but remain good friends.
Tienen puntos de vista opuestos sobre la política, pero siguen siendo buenos amigos.
C2 adjective /ˌoʊpəˈlɛsənt/

opalescent

opalescente
Meaning
showing or reflecting a milky, iridescent light like an opal
Example
The opalescent sky glowed with shades of pink and blue.
El cielo opalescente brillaba con tonos de rosa y azul.
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.
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.
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.
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.
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 adjective /əˈkeɪ.ʒən.əl/

Occasional

ocasional
Meaning
occurring infrequently or irregularly; happening from time to time
Example
She enjoys occasional walks in the park.
Ella disfruta de paseos ocasionales en el parque.
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.
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 /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.
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.
C2 adjective /ˈəʊ.dər.əs/

Odorous

fragante; aromático
Meaning
having a strong smell; fragrant; aromatic
Example
The garden was filled with odorous flowers.
El jardín estaba lleno de flores fragantes.
B2 noun /ˈoʊ.vər ɡroʊθ/

Over growth

crecimiento excesivo
Meaning
excessive growth beyond normal size; too much development or expansion
Example
The overgrowth of weeds made the garden look untidy.
El crecimiento excesivo de las malas hierbas hizo que el jardín pareciera descuidado.
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 /əbˈdʒɛktər/

objector

opositor
Meaning
a person who expresses opposition or disapproval to something
Example
The objector raised his concerns during the town meeting.
El opositor expresó sus preocupaciones durante la reunión del consejo.
C1 adjective /əbˈtjuːs/

Obtuse

tonto; obtuso; lento de comprensión
Meaning
annoyingly insensitive or slow to understand; lacking in intelligence or perception
Example
He was being deliberately obtuse about the instructions.
Él estaba siendo deliberadamente obtuso sobre las instrucciones.
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.
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.
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.
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.
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.
B2 adjective /ˌfæʃ.ənd/

Outdated

desactualizado
Meaning
obsolete; no longer current
Example
This computer software is completely outdated.
Este software de computadora está completamente desactualizado.
A1 adjective /oʊˈkeɪ/

ok

está bien
Meaning
used to indicate agreement, approval, or understanding
Example
Okay, let's go to the park.
Está bien, vamos al parque.
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.
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 verb ˈɔːr.kɪ.streɪt

orchestrate

coordinar
Meaning
To plan or coordinate the elements of (a situation) to produce a desired effect, especially surreptitiously.
Example
He skillfully orchestrated the entire event.
Él organizó hábilmente todo el evento.
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 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 /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.
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.
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.
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.
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 /ˈɔːrdʒi/

orgy

fiesta desmedida
Meaning
A wild party involving excessive indulgence, especially of a sexual nature.
Example
The novel described a scandalous orgy in a wealthy mansion.
La novela describió una orgía escandalosa en una mansión rica.
C1 adjective /əbˈnɒkʃəs/

Obnoxious

odioso
Meaning
extremely unpleasant; offensive; annoying
Example
His obnoxious behavior at the party annoyed everyone.
Su comportamiento odioso en la fiesta molestó a todos.
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.
B2 adjective + noun ˈɒptɪməl ˈtempərətʃər

optimal temperature

temperatura óptima
Meaning
The best or most favorable temperature for a particular purpose
Example
Winter provides optimal temperature for farming.
El invierno proporciona la temperatura óptima para la agricultura.
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.
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.
B2 verb /ˌoʊvərˈduː/

overdo

exagerar
Meaning
to do something too much; to exaggerate or carry to excess
Example
Don't overdo the exercise on your first day at the gym.
No exageres con el ejercicio en tu primer día en el gimnasio.
B2 noun /ˌɒb.zəˈveɪ.ʃənz/

observations

observación
Meaning
The action or process of observing something carefully.
Example
Observations of distant galaxies provide new insights.
Las observaciones de galaxias distantes proporcionan nuevas ideas.
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 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.
B2 verb /əˈblaɪdʒ/

oblige

obligar
Meaning
to compel or require someone to do something; to help or do a favor
Example
I would be happy to oblige you with the information you need.
Estaría feliz de obligarte con la información que necesitas.
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.
B2 verb /ˌoʊvərˈsiː/

oversee

supervisar
Meaning
to supervise or watch over something; to manage and direct
Example
The manager will oversee the entire construction project.
El gerente supervisará todo el proyecto de construcción.
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.
C1 noun /ˈɔr.i.ənt/

Orient

Oriente, especialmente los países de Asia oriental
Meaning
the East, especially countries of eastern Asia; to determine one's position or direction
Example
Many spices come from the Orient.
Muchas especias vienen del Oriente.
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.
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.
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.
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 /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 adjective /əbˈzɜːrvənt/

Observant

observador
Meaning
quick to notice things; watchful; attentive
Example
The observant detective noticed every small detail at the crime scene.
El detective observador notó cada pequeño detalle en la escena del crimen.
A1 pronoun /ˈʌðərz/

others

otros
Meaning
people or things distinct from the ones already mentioned or known
Example
I like to spend time with others.
Me gusta pasar tiempo con otros.
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 verb /ˌaʊtməˈnuːvər/

outmaneuver

superar astutamente
Meaning
to gain an advantage over an opponent by skillful or clever action
Example
The smaller company managed to outmaneuver its larger rival.
La empresa más pequeña logró superar astutamente a su rival más grande.
A2 noun /ˈɒpərə/

opera

ópera
Meaning
a dramatic performance in which the actors sing most of their lines
Example
We watched a beautiful opera at the theater last night.
Vimos una hermosa ópera en el teatro anoche.
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 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.
A2 modal verb /ɔːt/

ought

debería
Meaning
Used to indicate duty, correctness, or moral obligation.
Example
You ought to respect your elders.
Deberías respetar a tus mayores.
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 noun /əˈprəʊ.bri.əm/

opprobrium

desprecio, oprobio
Meaning
Harsh criticism or public disgrace.
Example
The scandal brought opprobrium on the politician.
El escándalo trajo desprecio al político.
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.
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.
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 /ˈaʊtskɜːrts/

outskirts

afueras de la ciudad
Meaning
The outer parts of a town or city, away from the center.
Example
They moved to the outskirts of the city for a quieter life.
Se mudaron a las afueras de la ciudad para una vida más tranquila.
B2 noun /ˈɔːkɪstrə/

orchestra

orquesta
Meaning
a large group of musicians playing different instruments together
Example
The orchestra performed beautifully at the concert.
La orquesta actuó maravillosamente en el concierto.
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.
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 verb /aʊtˈwɪt/

outwit

superar con astucia
Meaning
to defeat or gain an advantage over someone by being more clever or cunning
Example
The fox managed to outwit the hunters.
El zorro logró engañar a los cazadores.
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.
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 /ɒdz/

odds

probabilidad
Meaning
the likelihood or probability of something happening; chances for or against something
Example
The odds of winning the lottery are very low.
Las probabilidades de ganar la lotería son muy bajas.
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.
B1 adverb /əˈrɪdʒɪnəli/

originally

originalmente
Meaning
in the beginning, at first
Example
Originally, she wanted to be a doctor.
Originalmente, ella quería ser doctora.
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.
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 /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 /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.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 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.
C1 adjective /ˌəʊ.vərˈɑː.tʃɪŋ/

overarching

global, abarcante, integral
Meaning
Comprehensive or all-embracing; forming an arch over something.
Example
The overarching theme of the book is human resilience.
El tema global del libro es la resistencia humana.
B2 adjective /ˈɔː.rəl/

Oral

oral; relacionado con la boca
Meaning
spoken rather than written; relating to the mouth
Example
The oral examination will test your speaking skills.
El examen oral evaluará tus habilidades de hablar.
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.
C2 noun /ˌɔːrnɪˈθɒlədʒɪst/

ornithologist

ornitólogo
Meaning
a scientist who studies birds
Example
The ornithologist spent years studying migratory birds.
El ornitólogo pasó años estudiando aves migratorias.
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 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.
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.
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.
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.
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.
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, verb /əbˈskjʊr/

obscure

oscuro
Meaning
Not clearly expressed or understood; to make something difficult to see or understand.
Example
The meaning of the poem was obscure to most readers.
El significado del poema era oscuro para la mayoría de los lectores.
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.
A2 verb /ˈɔːfər/

offer

ofrecer
Meaning
to present something for acceptance or rejection; to propose
Example
She offered to help with the project.
Ella se ofreció a ayudar con el proyecto.
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.
C1 adjective /ˌoʊvərˈbɛrɪŋ/

overbearing

opresivo
Meaning
unpleasantly or arrogantly domineering
Example
His overbearing attitude made everyone uncomfortable.
Su actitud opresiva hizo que todos se sintieran incómodos.
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.
A2 adjective /ˈaʊtdɔːr/

outdoor

al aire libre
Meaning
situated, existing, or done outside a building
Example
We planned an outdoor picnic for the weekend.
Planeamos un picnic al aire libre para el fin de semana.
C2 verb /əbˈtruːd/

obtrude

obstruir
Meaning
to force oneself or one's ideas into a situation uninvited or inappropriately
Example
He didn’t want to obtrude into their private conversation.
Él no quería obstruir su conversación privada.
C2 noun /oʊd/

ode

oda
Meaning
a lyrical poem, often expressing praise or strong emotions
Example
The poet wrote an ode to the beauty of nature.
El poeta escribió una oda a la belleza de la naturaleza.
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.
B2 adjective; verb (past participle) /ˈɒkjʊpaɪd/

occupied

ocupado
Meaning
being in use or taken; filled or lived in; controlled or held by force
Example
The room is occupied, so please wait outside.
La habitación está ocupada, por favor espere afuera.
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 verb /oʊ/

owe

deber
Meaning
to be under obligation to pay or repay; to be indebted
Example
I owe my success to my parents' support.
Le debo mi éxito al apoyo de mis padres.
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.