opalescent
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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 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.
C1 adjective /əˈblaɪdʒɪŋ/

obliging

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

octagon

octágono
Meaning
A polygon with eight sides and eight angles.
Example
The stop sign is shaped like an octagon.
La señal de alto tiene forma de octágono.
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 /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.
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.
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.
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.
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.
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.
B2 noun /ˈɒkjʊpənt/

occupant

ocupante
Meaning
A person who resides in or is present in a house, vehicle, seat, or place.
Example
The car had three occupants at the time of the accident.
El coche tenía tres ocupantes en el momento del accidente.
B2 adverb /ˈəʊvəli/

overly

excesivamente
Meaning
to an excessive degree or extent
Example
She was overly concerned about the results.
Ella estaba excesivamente preocupada por los resultados.
C1 adjective /ˌɔː.riˈen.təl/

Oriental

relativo a los países del Este de Asia; oriental
Meaning
relating to the countries of East Asia; eastern
Example
The museum has a beautiful collection of oriental art.
El museo tiene una hermosa colección de arte oriental.
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.
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.
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.
B2 noun /əˌrɪʒ.əˈnæl.ə.ti/

Originality

originalidad
Meaning
the quality of being novel or unusual; the ability to think independently and creatively
Example
The artist's work showed great originality and creativity.
La obra del artista mostró gran originalidad y creatividad.
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.
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.
B2 noun /ˈaʊtˌbreɪk/

outbreak

brote
Meaning
a sudden start or occurrence of something unpleasant, like disease or violence
Example
There was an outbreak of flu in the city.
Hubo un brote de gripe en la ciudad.
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.
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.
C2 noun /ˈɑb.lə.kwi/

Obloquy

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

overtake

adelantar
Meaning
to catch up with and pass someone or something; to surpass
Example
The runner managed to overtake his competitor in the final lap.
El corredor logró adelantar a su competidor en la última vuelta.
C1 noun /əbˈzɜːvəns/

observance

observancia
Meaning
The practice of following a custom, rule, or religious law.
Example
The festival is held in observance of a centuries-old tradition.
El festival se celebra en observancia de una tradición centenaria.
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.
B2 adverb /ˈaʊtraɪt/

Outright

directamente; completamente; sin reservas
Meaning
completely; directly; without reservation or concealment
Example
She rejected the proposal outright.
Ella rechazó la propuesta directamente.
C2 noun /ˌɔːrnɪˈθɑːlədʒi/

ornithology

ornitología
Meaning
the scientific study of birds
Example
She pursued ornithology to understand the migration patterns of birds.
Ella persiguió la ornitología para entender los patrones de migración de los pájaros.
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.
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.
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 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.
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.
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 /ˈoʊvərˌsiːər/

overseer

supervisor
Meaning
a person who supervises work or workers; a manager
Example
The overseer made sure the workers followed safety rules.
El supervisor se aseguró de que los trabajadores siguieran las reglas de seguridad.
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.
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.
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 noun /oʊˈbɪt.ʃu.er.i/

Obituary

obituario
Meaning
a notice of someone's death published in a newspaper; biographical account of deceased person
Example
The newspaper published his obituary yesterday.
El periódico publicó su obituario ayer.
C1 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.
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.
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 /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.
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.
B2 noun /ˈɒs.trɪtʃ/

Ostrich

avestruz
Meaning
a large flightless bird native to Africa with long legs and neck
Example
The ostrich is the world's largest bird.
El avestruz es el pájaro más grande del mundo.
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.
C2 verb /oʊˈpaɪn/

opine

expresar una opinión
Meaning
to express an opinion or belief
Example
The professor opined that the policy would fail.
El profesor opinó que la política fracasaría.
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 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 /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 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.
B2 adjective /ˌoʊvərˈwɛlmɪŋ/

overwhelming

abrumador
Meaning
Very intense; overpowering.
Example
Large tasks can feel overwhelming.
Las grandes tareas pueden sentirse abrumadoras.
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.
B2 noun /ˈaʊtˌskɜːrt/

outskirt

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

Omniscient

omnisciente
Meaning
having complete knowledge; all-knowing
Example
The narrator in the novel appears to be omniscient, knowing every character's thoughts.
El narrador en la novela parece ser omnisciente, conociendo todos los pensamientos de los personajes.
C1 noun /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.
B1 verb /ˈɒpəreɪtɪŋ/

operating

operando
Meaning
to control or manage the functioning of something
Example
The company has been operating in this market for five years.
La compañía ha estado operando en este mercado durante cinco años.
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 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.
C1 noun ˈaʊt.sɔːr.sɪŋ

outsourcing

externalización
Meaning
The practice of having certain job functions done outside a company instead of having an in-house department or employee handle them.
Example
Many companies use outsourcing to reduce labor costs.
Muchas empresas utilizan la externalización para reducir los costos laborales.
B2 noun /ˈaʊt.saɪ.dər/

Out-sider

extranjero
Meaning
a person who does not belong to a particular group; someone not accepted by a group
Example
As an outsider, he found it difficult to understand their traditions.
Como extranjero, le resultó difícil entender sus tradiciones.
B2 adverb /ˈɒdli/

oddly

extrañamente
Meaning
in a strange or unusual way; unexpectedly
Example
Oddly, he didn’t seem upset by the bad news.
Extrañamente, no parecía molesto por la mala noticia.
C2 adjective /ˈoʊ.pən ˈhɑrt.ɪd/

Open-hearted

de corazón abierto; generoso y sincero; cálidamente receptivo;
Meaning
Kind and generous; sincere and honest; warmly receptive;
Example
She welcomed the strangers with an open-hearted smile and invited them for dinner.
Ella dio la bienvenida a los extraños con una sonrisa de corazón abierto e invitó a cenar.
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.
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 /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 adjective /əˈblɪɡ.ə.tɔː.ri/

obligatory

obligatorio
Meaning
Required by a legal, moral, or other rule; compulsory.
Example
Wearing a seatbelt is obligatory in most countries.
Usar el cinturón de seguridad es obligatorio en la mayoría de los países.
B2 noun /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.
A2 noun /ˈɔr.dər/

Order

orden; secuencia
Meaning
a command or instruction; the arrangement of things following a particular sequence
Example
The teacher gave an order to sit down quietly.
El maestro dio una orden para sentarse tranquilamente.
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.
B2 noun /ˈɔr.fən.ɪʒ/

Orphanage

orfanato
Meaning
an institution for the care and education of children who have lost their parents
Example
The charity built a new orphanage for homeless children.
La caridad construyó un nuevo orfanato para niños sin hogar.
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.
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.
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 adjective /əbˈsɛsɪv/

obsessive

obsesivo
Meaning
Relating to or characterized by an obsession; thinking about something too much.
Example
He has an obsessive interest in cleanliness.
Él tiene un interés obsesivo en la limpieza.
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 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 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 verb /ˈɒp.tɪ.maɪz/

optimize

optimizar
Meaning
To make the best or most effective use of a situation, opportunity, or resource.
Example
The company is working to optimize its supply chain.
La empresa está trabajando para optimizar su cadena de suministro.
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.
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.
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.
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 /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 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 /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 verb /ˌaʊtˈweɪ/

outweigh

ser más importante
Meaning
To be more important, valuable, or significant than something else.
Example
The benefits of the new policy outweigh the risks.
Los beneficios de la nueva política superan los riesgos.
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.
C1 noun ˌɒp.tɪ.maɪˈzeɪ.ʃən

optimization

optimización
Meaning
Improving processes to increase performance and efficiency.
Example
SEO optimization helps websites rank higher on search engines.
La optimización de SEO ayuda a los sitios web a obtener un rango más alto en los motores de búsqueda.
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.
C2 noun /ˌɒstɛnˈteɪʃən/

ostentation

ostentación
Meaning
excessive display of wealth or knowledge intended to attract admiration or envy
Example
The billionaire’s party was full of ostentation and luxury.
La fiesta del multimillonario estaba llena de ostentación y lujo.
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.
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.
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.
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.
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.
B2 adverb /ˈoʊpənli/

Openly

abiertamente; públicamente
Meaning
in a frank and honest way; without concealment; publicly
Example
She spoke openly about her struggles with mental health.
Ella habló abiertamente sobre sus luchas con la salud mental.
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.
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.
B1 adjective /ˌoʊld ˈfæʃənd/

old-fashioned

anticuado
Meaning
not modern; belonging to an earlier time
Example
He still wears an old-fashioned hat.
Él todavía usa un sombrero anticuado.
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.
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.
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.
C2 noun /ˈoʊpiət/

opiate

opiáceo
Meaning
a drug containing opium or its derivatives, used to relieve pain or cause sleep
Example
The doctor prescribed an opiate to relieve the patient's pain.
El médico recetó un opiáceo para aliviar el dolor del paciente.
C2 adjective /ɒmˈnɪp.ə.tənt/

omnipotent

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