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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.
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 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 /ˈɔːrdɪnəl/

ordinal

ordinal
Meaning
Relating to the order or position of something in a sequence (first, second, third, etc.).
Example
The ordinal number 'third' indicates position in a sequence.
El número ordinal 'tercero' indica la posición en una secuencia.
C2 noun /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.
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.
B1 adjective /ˌoʊvərˈweɪt/

overweight

sobrepeso
Meaning
heavier than is considered healthy or normal
Example
The doctor advised him to lose weight as he was overweight.
El doctor le aconsejó perder peso ya que tenía sobrepeso.
C1 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 /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 /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 /ˌɑːpərˈtuːnɪst/

opportunist

oportunista
Meaning
A person who takes advantage of situations for personal gain, often disregarding principles.
Example
He is seen as an opportunist who always puts his interests first.
Se le ve como un oportunista que siempre pone sus intereses primero.
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.
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 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.
B2 noun /ɔːˈræŋ.ʊˌtæŋ/

Orang-Outang

orangután
Meaning
a large arboreal ape with long reddish hair, long arms, and hooked hands and feet, native to Borneo and Sumatra
Example
The orangutan swings gracefully through the forest canopy.
El orangután se balancea graciosamente a través del dosel del bosque.
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.
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.
C1 verb /ˌoʊvərˈθroʊ/

overthrow

felicidad
Meaning
To remove a leader or government from power, often by force.
Example
The rebels planned to overthrow the corrupt regime.
No pudo esconder su felicidad cuando recibió el premio.
C1 adjective /əˈkʌlt/

occult

oculto
Meaning
Relating to mysterious, supernatural, or magical powers and practices.
Example
She had always been fascinated by the occult and its hidden knowledge.
Ella siempre estuvo fascinada por lo oculto y su conocimiento oculto.
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.
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.
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.
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.
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 noun /ˌɑːpərˈtuːnɪzəm/

opportunism

oportunismo
Meaning
The practice of taking advantage of opportunities regardless of principles or ethics.
Example
His decision was driven by opportunism, not values.
Su decisión fue impulsada por el oportunismo, no por los valores.
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.
A1 noun /ɒkˈtoʊbər/

october

octubre
Meaning
the tenth month of the year in the Gregorian calendar
Example
The weather becomes cooler in October.
El clima se vuelve más fresco en octubre.
C2 adjective /ˌɒbsəˈlɛsnt/

obsolescent

obsoleto
Meaning
Becoming outdated or on the way to becoming obsolete.
Example
The obsolescent technology could not compete with modern devices.
La tecnología obsoleta no pudo competir con los dispositivos modernos.
C2 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 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.
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.
A1 adverb /aʊt/

out

fuera
Meaning
moving or appearing away from the inside or center; not at home or present
Example
He stepped out of the room quietly.
Él salió de la habitación en silencio.
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.
B1 noun /ˈɑː.lɪv/

Olive

aceituna
Meaning
a small oval fruit with a hard pit, typically green or black, used for eating or making oil
Example
Olive oil is considered one of the healthiest cooking oils available.
El aceite de oliva se considera uno de los aceites de cocina más saludables disponibles.
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 verb /ˈɑːblɪˌɡeɪt/

obligate

obligar
Meaning
to bind legally or morally; to compel someone to do something
Example
The contract obligates the company to provide timely service.
El contrato obliga a la empresa a proporcionar un servicio puntual.
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.
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.
C1 adjective /ˌɒstɛnˈteɪʃəs/

ostentatious

ostentoso
Meaning
Characterized by a showy or pretentious display intended to impress others.
Example
He wore an ostentatious gold chain to the party.
Llevaba una cadena de oro ostentosa en la fiesta.
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 adjective /ˌfæʃ.ənd/

Outdated

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

originate

originar
Meaning
to come into existence; to begin; to create or produce
Example
The tradition originated in ancient times.
La tradición se originó en tiempos antiguos.
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.
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.
A2 noun /ɔɪl/

Oil

aceite
Meaning
a viscous liquid derived from petroleum or plants, used for cooking or fuel
Example
Heat the oil in a pan before adding the vegetables.
Calienta el aceite en una sartén antes de añadir las verduras.
C2 adjective /əˈfɪʃəs/

officious

entrometido
Meaning
Excessively eager to offer unwanted help or advice; meddlesome.
Example
The officious guard kept interrupting the visitors with unnecessary instructions.
El guardia entrometido interrumpía a los visitantes con instrucciones innecesarias.
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.
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.
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 /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.
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 adjective /əˈprəʊ.bri.əs/

opprobrious

despectivo
Meaning
Expressing strong criticism or scorn.
Example
He made opprobrious remarks about his opponent.
Él hizo comentarios despectivos sobre su oponente.
C2 adjective /ˈɒf.biːt/

offbeat

inusual
Meaning
Unusual, unconventional, or different from the norm.
Example
She has a very offbeat sense of humor.
Ella tiene un sentido del humor muy inusual.
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.
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.
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 /ˌaʊtˈstrɛtʃ/

outstretch

extender
Meaning
To extend or stretch something outward.
Example
He outstretched his hand to help her up.
Él extendió su mano para ayudarla a levantarse.
B2 verb /ˌoʊvərˈlʊk/

overlook

pasar por alto
Meaning
to fail to notice or consider something; to have a view from above
Example
It's easy to overlook small details when you're in a hurry.
Es fácil pasar por alto los pequeños detalles cuando tienes prisa.
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.
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.
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 ˈaʊt.pʊt

output

producción
Meaning
The amount of something produced by a person, machine, or industry.
Example
Climate change reduces agricultural output.
El cambio climático reduce la producción agrícola.
B1 verb অকার্স

occurs

sucede
Meaning
Happens or takes place, especially as a result of something.
Example
Snowfall occurs in regions with freezing temperatures.
La nieve ocurre en regiones con temperaturas bajo cero.
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.
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 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.
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.
A1 preposition /ʌv/

of

de
Meaning
expressing the relationship between a part and a whole
Example
The book is on the table, in front of the window.
El libro está sobre la mesa, frente a la ventana.
B2 noun /əbˈdʒek.ʃən/

Objection

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

obsequy

obsequio
Meaning
A funeral rite, usually used in plural form obsequies.
Example
The village gathered for the obsequy of their beloved teacher.
El pueblo se reunió para el obsequio de su querido maestro.
C1 noun ˈoʊʃən əˌsɪdɪfɪˈkeɪʃən

ocean acidification

acidificación oceánica
Meaning
The ongoing decrease in the pH of the Earth's oceans, caused by the absorption of carbon dioxide from the atmosphere.
Example
Ocean acidification is caused by atmospheric CO2 absorption.
La acidificación oceánica es causada por la absorción de CO2 atmosférico.
A1 conjunction /ɔːr/

or

o
Meaning
used to link alternatives
Example
You can have tea or coffee.
Puedes tomar té o café.
C1 verb /ˌoʊvərˈruːl/

overrule

anular
Meaning
to reject or disallow by exercising one's superior authority; to override a decision
Example
The judge overruled the objection from the defense attorney.
El juez anuló la objeción del abogado defensor.
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.
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.
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 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.
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.
B1 noun əbˈdʒek.tɪv

objective

objetivo
Meaning
A thing aimed at or sought; a goal.
Example
The main objective is to test sustainability.
El objetivo principal es probar la sostenibilidad.
B2 noun /ˈaʊtlet/

outlet

salida
Meaning
a means by which something is released, expressed, or distributed
Example
Art is a great outlet for emotions.
El arte es una gran salida para las emociones.
B2 noun /ˈaʊtbɜːrst/

outburst

explosión repentina de ira o emoción
Meaning
a sudden release of strong emotion or activity
Example
She had an angry outburst during the meeting.
Ella tuvo una explosión de ira durante la reunión.
B2 adjective /aʊtˈreɪdʒəs/

outrageous

atroz
Meaning
Shockingly bad or excessive; very unusual or amusing.
Example
The comedian told an outrageous joke.
El comediante contó un chiste atroz.
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 adjective /ˈɒsiəs/

osseous

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

Overlet

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

Oppressive

opresivo
Meaning
Harsh and authoritarian; overwhelming; causing distress; tyrannical;
Example
The oppressive heat made it difficult to work outside during the summer.
El calor opresivo dificultaba trabajar afuera durante el verano.
C1 verb /ˌoʊvərˈriːtʃ/

overreach

sobreesfuerzo
Meaning
to go beyond what is proper, acceptable, or achievable; to overextend
Example
The politician overreached by making promises he couldn't keep.
El político hizo un esfuerzo excesivo al hacer promesas que no pudo cumplir.
C1 adjective /ˌəʊvərˈstɪmjʊˌleɪtɪd/

overstimulated

sobrestimulado
Meaning
Excessively excited or aroused, overwhelmed by too much stimulus.
Example
Overstimulated minds can lead to burnout and decreased productivity.
Las mentes sobrestimuladas pueden conducir al agotamiento y a una menor productividad.
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.
B2 noun /əˈfens/

Offence

delito; infracción; agravio
Meaning
a breach of law or rule; an annoyance or resentment
Example
Stealing is a serious offence punishable by law.
El robo es un delito grave castigado por la ley.
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 /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.
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 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.
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 /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.
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.
B2 noun /oʊˈbiː.di.əns/

Obedience

obediencia
Meaning
compliance with an order, request, or law; submission to authority
Example
Children should show obedience to their parents.
Los niños deben mostrar obediencia a sus padres.
A1 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.
B1 adjective /əˈbiː.di.ənt/

Obedient

obediente
Meaning
willing to comply with orders or instructions; submissive
Example
The obedient student always follows the teacher's instructions.
El estudiante obediente siempre sigue las instrucciones del profesor.
C1 noun /ˈɒktɪv/

octave

octava
Meaning
A series of eight musical notes, or the interval between one musical pitch and another with double its frequency.
Example
The singer's voice could easily reach the higher octave.
La voz del cantante podría alcanzar fácilmente la octava más alta.
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 /ˈɒpəreɪtər/

operator

operador
Meaning
a person who operates equipment, a business, or controls something
Example
The machine operator ensured that everything ran smoothly.
El operador de la máquina se aseguró de que todo funcionara sin problemas.
B2 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.
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.
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.
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 verb /ˌoʊvərˈstraɪd/

overstride

cruzar dando pasos largos
Meaning
To stride over something; to step across with long steps.
Example
He managed to overstride the narrow stream with ease.
Él logró cruzar el estrecho arroyo con facilidad.
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.
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.
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.
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 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.
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.
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 verb /ˈoʊɡəl/

ogle

mirar lascivamente
Meaning
To look at someone with obvious sexual interest.
Example
He kept ogling the models on the runway.
Él no podía dejar de mirar las modelos en la pasarela.