operational
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B2 adjective ˌɒp.ərˈeɪ.ʃən.əl

operational

operativo
Meaning
In working order; ready for use.
Example
The space project will be operational by 2025.
El proyecto espacial estará operativo para 2025.
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.
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.
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.
B1 noun /ˌɒpəˈreɪʃən/

operation

operación
Meaning
an act or process of functioning or operating
Example
The hospital performed a successful operation.
El hospital realizó una operación exitosa.
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!
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 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 /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.
A2 noun əˈlɪm.pɪk ɡeɪmz

Olympic Games

juegos olímpicos
Meaning
The world's largest international sports competition held every four years, bringing together athletes from different countries to compete in various sports.
Example
The Olympic Games bring together the world's top athletes.
Los Juegos Olímpicos reúnen a los mejores atletas del mundo.
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.
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.
C1 noun /ˈɑːdəsi/

odyssey

viaje largo
Meaning
a long, adventurous journey; a series of experiences
Example
Her career has been an odyssey of challenges and achievements.
Su carrera ha sido una odisea de desafíos y logros.
C2 adjective /əˈrækjələr/

oracular

oracular
Meaning
Resembling an oracle; giving wise, mysterious, or prophetic statements
Example
Her oracular words left the audience deep in thought.
Sus palabras oraculares dejaron a la audiencia profundamente pensativa.
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.
C1 noun /ˈaʊtˌkraɪ/

outcry

protesta
Meaning
A strong expression of public anger or disapproval.
Example
The decision sparked an outcry among the citizens.
La decisión provocó una protesta entre los ciudadanos.
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 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.
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.
A2 adverb; noun /ˌaʊtˈdɔːrz/

outdoors

al aire libre
Meaning
outside a building; the natural environment outside
Example
We spent the whole afternoon outdoors enjoying the fresh air.
Pasamos toda la tarde al aire libre disfrutando del aire fresco.
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 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.
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 /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.
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 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 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 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 əˈblɪv.i.ən

oblivion

olvido, destrucción, desaparición
Meaning
The state of being unaware or unconscious of what is happening; complete forgetfulness.
Example
His name faded into oblivion over time.
Su nombre se desvaneció en el olvido con el tiempo.
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.
A1 adjective /ˈʌðər/

other

otro
Meaning
used to refer to something different from the one already mentioned or known
Example
I don't want this one, I will take the other one.
No quiero este, tomaré el otro.
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.
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 /ˈoʊtˌmiːl/

oatmeal

avena cocida
Meaning
A type of porridge made from ground oats, often eaten for breakfast.
Example
She eats a bowl of oatmeal every morning for breakfast.
Ella come un tazón de avena cocida todas las mañanas para el desayuno.
C1 adjective /əbˈstrʌk.tɪv/

Obstructive

obstructivo
Meaning
deliberately creating difficulties or preventing progress; hindering or blocking something
Example
The obstructive policies hindered economic growth.
Las políticas obstructivas obstaculizaron el crecimiento económico.
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 /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.
B2 adjective /ˈɔɪl.i/

Oily

oleoso; cubierto de aceite; grasoso
Meaning
covered with oil; containing oil; greasy
Example
Her oily skin needs special care.
Su piel aceitosa necesita cuidados especiales.
C1 adjective /ˌɔːrθəˈpiːdɪk/

orthopedic

relacionado con la corrección de deformidades óseas o musculares
Meaning
Relating to the correction of deformities of bones or muscles.
Example
She visited an orthopedic surgeon for her back pain.
Ella visitó a un cirujano ortopédico por el dolor en la espalda.
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.
C2 noun /ɒmˈnɪpətəns/

omnipotence

omnipotencia
Meaning
The quality of having unlimited power or authority.
Example
Many religions describe God’s omnipotence as absolute.
Muchas religiones describen la omnipotencia de Dios como absoluta.
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.
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.
A1 conjunction /ɔːr/

or

o
Meaning
used to link alternatives
Example
You can have tea or coffee.
Puedes tomar té o café.
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.
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.
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.
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.
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.
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.
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 adjective /ˌfæʃ.ənd/

Outdated

desactualizado
Meaning
obsolete; no longer current
Example
This computer software is completely outdated.
Este software de computadora está completamente desactualizado.
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.
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.
B2 verb /əbˈteɪn/

obtain

obtener
Meaning
to get or acquire something
Example
You need to obtain a visa before traveling abroad.
Necesitas obtener una visa antes de viajar al extranjero.
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 /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 /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.
C1 noun /ˈɒstrəsɪzəm/

ostracism

ostracismo
Meaning
The act of excluding someone from a group or society.
Example
The student faced ostracism after breaking the rules.
El estudiante enfrentó el ostracismo después de romper las reglas.
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.
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!
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.
C2 noun /ˌɔːrdɪˈneɪʃən/

ordination

ordenación
Meaning
The ceremony of conferring holy orders or official religious authority.
Example
The church held a special service for the ordination of new priests.
La iglesia celebró un servicio especial para la ordenación de nuevos sacerdotes.
B2 noun /ˈɔːrnəmənt/

ornament

adorno
Meaning
A decorative object that adds beauty to something.
Example
The Christmas tree was decorated with colorful ornaments.
El árbol de Navidad estaba decorado con adornos de colores.
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.
B2 verb /ˌoʊvərˈpeɪ/

overpay

pagar en exceso
Meaning
To pay more than is necessary or reasonable.
Example
She realized she had overpaid for the concert tickets.
Ella se dio cuenta de que había pagado de más por las entradas del concierto.
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 əˈblɪv.i.əs

oblivious

despreocupado
Meaning
Being completely unaware of surrounding events.
Example
He was oblivious to the noise around him while reading.
Él no se dio cuenta del ruido a su alrededor mientras leía.
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.
C1 adjective /ˌɑːpərˈtuːn/

opportune

momento oportuno
Meaning
Happening at a suitable or convenient time.
Example
She arrived at an opportune moment to help.
Llegó en un momento oportuno para ayudar.
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.
C2 noun /ˈɔːrɪndʒfɪn ˈleɪbiːoʊ/

Orangefin labeo

labeo de aleta naranja
Meaning
a freshwater fish species native to South Asian rivers, commonly found in Bangladesh and India
Example
The orangefin labeo is an important food fish in Bangladesh.
El labeo de aleta naranja es un pez alimenticio importante en Bangladesh.
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.
B2 noun /əˈpoʊ.nənt/

Opponent

oponente; rival
Meaning
a person who disagrees with or resists a proposal or practice; someone who competes against another
Example
The chess player defeated his strongest opponent.
El jugador de ajedrez derrotó a su oponente más fuerte.
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.
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.
C2 noun /ˈɒlɪv brɑːntʃ/

olive-branch

rama de olivo
Meaning
A symbol of peace or reconciliation; an offer to end conflict.
Example
He extended an olive-branch to his rival after years of hostility.
Extendió una rama de olivo a su rival después de años de hostilidad.
C1 adjective /ɒˈstɛnsəbl/

ostensible

aparente
Meaning
stated or appearing to be true, but not necessarily so
Example
His ostensible reason for leaving was illness, but many doubted it.
Su aparente razón para irse era la enfermedad, pero muchos lo dudaron.
B2 noun ˈəʊ.və.hed

overhead

gastos generales
Meaning
Ongoing business expenses not directly attributable to creating a product or service.
Example
The company reduced its overhead to increase profits.
La empresa redujo sus gastos generales para aumentar las ganancias.
C1 noun ˌɒb.səˈlɛs.əns

obsolescence

obsolescencia
Meaning
The process of becoming obsolete or outdated and no longer used.
Example
The rapid advancement of technology leads to the obsolescence of old devices.
El rápido avance de la tecnología provoca la obsolescencia de los dispositivos antiguos.
C1 adjective /əbˈdʒek.ʃən.ə.bəl/

Objectionable

objecionable
Meaning
arousing distaste or opposition; unpleasant or offensive
Example
His objectionable behavior made everyone uncomfortable.
Su comportamiento objetable hizo que todos se sintieran incómodos.
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 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.
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.
B2 verb /ˌoʊvərˈiːt/

overeat

felicidad
Meaning
To eat more food than the body needs.
Example
She tends to overeat when she is stressed.
Ella no pudo ocultar su felicidad cuando recibió el premio.
C1 adjective /ˌɒmnɪˈprezənt/

omnipresent

omnipresente
Meaning
(of God) present everywhere at the same time.
Example
Social media has become an omnipresent force in modern society.
Las redes sociales se han convertido en una fuerza omnipresente en la sociedad moderna.
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.
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 /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.
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.
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.
A2 noun /əˈlɪmpɪks/

olympics

Juegos Olímpicos
Meaning
an international sports competition held every four years with athletes from many countries
Example
The Olympics bring athletes from all over the world together.
Los Juegos Olímpicos reúnen a atletas de todo el mundo.
C2 adjective /ˈɒpjʊlənt/

opulent

opulento
Meaning
Ostentatiously rich, luxurious, or lavish.
Example
They hosted an opulent wedding with gold decorations.
Organizaron una boda opulenta con decoraciones doradas.
C2 noun /ˈɔːfəl/

offal

vísceras
Meaning
the internal organs and entrails of an animal used as food; waste parts
Example
The butcher prepared sausages using pork offal.
El carnicero preparó salchichas usando vísceras de cerdo.
A1 pronoun, noun, adjective /wʌn/

one

uno
Meaning
the number equivalent to the sum of zero and one; a single person or thing
Example
Only one student answered the question.
Solo un estudiante respondió la pregunta.
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/verb /ˈoʊvərˌdoʊs/

overdose

sobredosis
Meaning
An excessive and dangerous amount of a drug; to take too much of a substance.
Example
He was rushed to the hospital after a drug overdose.
Fue llevado al hospital después de una sobredosis de drogas.
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.
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.
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 /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 /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.
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 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.
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.
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.
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.
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 adjective /ˈoʊdiəs/

odious

odioso
Meaning
extremely unpleasant or repulsive
Example
The dictator was remembered for his odious crimes.
El dictador fue recordado por sus odiosos crímenes.
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.
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.
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.
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.
B2 adjective /ˈɒnɡəʊɪŋ/

ongoing

en curso
Meaning
continuing; still in progress
Example
The ongoing project will finish next month.
El proyecto en curso terminará el próximo mes.
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.
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.
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 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.
C1 adjective /ˈaʊt.kɑːst/

Outcast

rechazado
Meaning
rejected by society; excluded person
Example
He felt like an outcast in his new school.
Él se sintió como un rechazado en su nueva escuela.
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.