A List of 250 + Spanish Words That Start With O

In this post you can find a collection of Spanish words that start with the O.

This list of Spanish vocabulary words that start with O features over 200 Spanish words. While it may not encompass every single Spanish word starting with O, it does include a selection of common words and not-so-common words that I believe will be valuable for English speakers to learn. These words can assist in daily conversations and enhance your Spanish language skills.

I will break up the Spanish O words into the following categories and each category will be alphabetical order. Click the category links below to jump right to that section!

Table of Contents

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Pronunciation of the Letter O in Spanish

In Spanish, the letter “o” is pronounced as a short vowel sound. It is similar to the “o” sound in the English word “hot.” The pronunciation of “o” in Spanish is consistent and does not change based on its position in a word.

Alright, now that you have a basic understanding of how to pronounce the letter O in Spanish, let’s move on to the following list of words in Spanish that start with O. I will sprinkle a few example sentences throughout the post where I see fit.

Spanish Nouns That Start With O

Below you can find a list of Spanish words that start with o that are nouns. Remember that if it is a singular masculine noun, it will care the article el beforehand, los for plural masculine nouns. For feminine nouns, use la for singular feminine nouns, and las for plural feminine nouns.

Below are a few tips to help you understand the gender of the noun.

In Spanish, the endings of nouns can often provide clues about their gender and can help determine whether they are masculine or feminine. While there are exceptions and irregularities, understanding common noun endings can be helpful when identifying the gender of a noun. Here are some key noun endings and their typical gender associations:

Masculine Noun Endings:
- -o: Many nouns ending in -o are masculine, such as “perro” (dog) or “libro” (book).
- -e: Some nouns ending in -e are masculine, like “coche” (car) or “café” (coffee).
- -or: Nouns ending in -or are typically masculine, such as “actor” (actor) or “doctor” (doctor).
Feminine Noun Endings:
- -a: Many nouns ending in -a are feminine, like “casa” (house) or “silla” (chair).
- -ción/-sión: Nouns ending in -ción or -sión are usually feminine, such as “información” (information) or “explosión” (explosion).
- -dad/-tad/-tud: Nouns ending in -dad, -tad, or -tud are typically feminine, like “amistad” (friendship) or “actitud” (attitude).

It’s important to note that these patterns are not absolute rules, and there are exceptions. Some words have the same form for both masculine and feminine, while others change meaning depending on the gender. Additionally, there are nouns with irregular endings that do not follow the usual patterns. To determine the gender of a noun, it is advisable to consult a dictionary or refer to specific language resources.

Spanish	English
Oasis	Oasis
Obsecación	Blindness
Obediencia	Obedience
Obesidad	Obesity
Obispo	Bishop
Obituario	Obituary
Objeción	Objection
Objetividad	Objectivity
Objeto	Object
Obligación	Obligation
Obra	Work of art, workmanship

Ej: El artista presentó su última obra en la galería de arte.

Ex: The artist presented his latest work at the art gallery.

Obrador	Bakery
Obraje	Sawmill, timberyard
Obrero	Worker
Obscenidad	Obscenity
Obsequio	Gift, present
Observación	Observation
Observador	Observer
Observancia	Observance
Observatorio	Observatory
Obsesión	Obsession
Obstáculo	Obstacle
Obstrucción	Obstruction
Obtención	Obtainment
Obviedad	Obvious remark
Ocasión	Occasion
Ocaso	Decline, sunset
Occidente	Western world
Océano	Ocean

Oceanografía	Oceanography
Oceanógrafo	Oceanographer
Ocio	Leisure
Octágono	Octogonal

Octava	Octave
Octavilla	Pamphlet, leaflet
Octubre	October
Ocupación	Occupation
Ocupante	Occupant
Ocurrencia	Idea
Odio	Hatred

Ej: Es importante promover el diálogo y la comprensión mutua para superar el odio y construir sociedades más pacíficas.

Ex: It is important to promote dialogue and mutual understanding to overcome hatred and build more peaceful societies.

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Odontología	Dentistry
Ofensa	Offense
Ofensa	Offense
Oferta	Offer
Ofertorio	Offertory
Oficial	Officer
Oficiante	Officiant, celebrant
Oficina	Office
Oficinista	Office worker
Oficio	Occupation
Ofrecimiento	Offer
Ofrenda	Tribute
Ogro	Ogre

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Oído	Ear
Ojeada	Glance
Ojeras	Dark ring around eyes
Ojo	Eye

Check out some idioms for ojo:

“Echar un ojo”: To take a look or glance at something.
“No pegar ojo”: To not be able to sleep. It refers to a situation where someone cannot sleep, usually due to worry or restlessness.
“Tener ojo clínico”: To have a keen eye or sharp perception. It means to have the ability to notice details or to be perceptive.
“Hacer ojitos”: To make eyes at someone. It refers to the act of using flirtatious or seductive eye gestures.

Ola	Ocean wave
Oleada	Big wave
Óleo	Oil
Olfato	Smell, sense of smell
Oligarca	Oligarch
Oligopolio	Oligarchy
Olimpiada	Olympiad
Oliva	Olive
Olivo	Olive tree
Olla	Pot, pan
Ombligo	Belly Button
Omisión	Omission
Omnipotencia	Omnipotence
Omoplato	Shoulder blade
Oncología	Oncology
Onda	Wave

Slang Word Alert

“Onda” is a slang term commonly used in Mexican Spanish and other Central American countries. It has various meanings depending on the context. Here are a few of its slang meanings:

Vibe/Atmosphere: “Onda” is often used to describe the overall atmosphere or vibe of a place or situation.

Example: “Este lugar tiene una buena onda” (This place has a good vibe).

Cool/Awesome: “Onda” can also be used to express something as cool, awesome, or great.

Example: “Esa canción está muy onda” (That song is really cool).

Friend/Friendly: “Onda” can refer to someone who is friendly or a friend.

Example: “Ella es una buena onda” (She is a friendly person).

Style/Appearance: In some contexts, “onda” can refer to someone’s style or appearance.

Example: “Tienes una onda muy original” (You have a very unique style).

It’s important to note that slang terms can have regional variations and evolve over time, so their meanings may differ in different contexts or countries.

Onza	Ounce
Ópalo	Opal
Opción	Option
Ópera	Opera
Operación	Operation
Operador	Operator
Operario	Operative, worker
Opiáceo	Opiate
Opinión	Opinion
Opio	Opium
Oponente	Opponent
Oportunidad	Opportunity
Oposición	Opposition
Opositor	Opponent
Opresión	Oppression
Optimismo	Optimism

Opulencia	Luxury
Oración	Prayer
Oráculo	Oracle
Orador	Speaker, orator
Orbe	Orb
Orden	Order
Ordenación	Order
Ordenador	Computer
Ordenamiento	Legislation
Ordeñadora	Milking machine
Orégano	Oregano

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Oreja	Ear
Organato	Orphanage
Organismo	Organism
Organizador	Organizer
Organización	Organization
Órgano	Organ
Orgasmo	Orgasm
Orgía	Orgy
Orgullo	Pride

Ej: Ella caminó hacia el escenario con orgullo, sintiéndose orgullosa de sus logros y sabiendo que había trabajado arduamente para llegar allí.

Ex: She walked onto the stage with pride, feeling proud of her accomplishments and knowing that she had worked hard to get there.

Orientación	Orientation
Oriente	East
Orificio	Orifice, hole
Origen	Origin
Original	Original
Orilla	Bank, shore

Ej: Nos sentamos en la orilla del río, disfrutando de la suave brisa y observando cómo el agua fluía tranquilamente.

Ex: We sat on the riverbank, enjoying the gentle breeze and watching the water flow peacefully.

Orines	Urine
Ornamento	Ornament
Ornato	adornment
Ornitorrinco	Platypus
Oro	Gold
Orquesta	Orchestra
Orquídea	Orchid
Ortodoxia	Orthodox
Ortografía	Spelling
Oruga	Caterpillar

Osadía	Daring, boldness
Oscilación	Swinging, swaying
Oscuridad	Dark
Oso	Bear
Ostentación	Ostentation, show, display
Ostra	Oyster
Otoño	Autumn

Ovación	Ovation
Óvalo	Oval
Ovario	Ovary
Oveja	Sheep
Ovillo	Wool ball
Ovulación	Ovulation
Oxidación	Rusting
Oxígeno	Oxygen
Oyente	Listener
Ozono	Ozone

Spanish Adjectives and Adverbs That Start With O

Spanish	English
Obcecado	Blind, mentally blinded
Obediente	Obedient
Obeso	Obese
Objetivamente	Objectively
Oblicuo	Oblique
Obligado	Forced
Obligatorio	Mandatory

Ej: Es obligatorio llevar mascarilla en lugares públicos para prevenir la propagación del virus.

Ex :It is mandatory to wear a mask in public places to prevent the spread of the virus.

Obsceno	Obscene
Obsequioso	Deferential
Obsesivo	Obsessive
Obseso	Obsessed
Obsoleto	Obsolete
Obstinado	Obstinate
Obtuso	Obtuse
Obviamente	Obviously
Obvio	Obvious
Ocasional	Chance, accidental
Occidental	Western
Océanico	Oceanic
Ochenta	Eighty
Ocho	Eight
Ochocientos	Eight hundred

Ocioso	Idle
Octagonal	Octogonal
Octavo	Eighth
Oculto	Hidden
Ocupacional	Occupational
Ocupado	Busy, taken
Ocurrente	Witty, entertaining
Odioso	Hateful
Oeste	Western
Ofendido	Offended
Oficial	Official
Oficialmente	Officially
Ojeroso	Haggard, to have bags under eyes
Olfativo	Olfactory
Oligárquico	Oligarchic
Oligofrénico	Mentally handicap
Olímpico	Olympic
Oloroso	Sweet-smelling, fragrant

Ej: El jardín está lleno de flores olorosas que perfuman todo el ambiente.

Ex:The garden is filled with fragrant flowers that perfume the entire atmosphere.

Olvidadizo	Forgetful
Omnímodo	All-embracing, absolute
Omnipotente	Omnipotent, all-powerful
Omnívoro	Omnivorous
Once	Eleven
Onceavo	Eleventh
Ondulado	Uneven, rough, rolling

Ej: Su cabello ondulado le da un aspecto natural y elegante.

Ex: Her wavy hair gives her a natural and elegant look.

Onzavo	Eleventh
Opaco	Opaque
Opcional	Optional
Operacional	Operational
Operante	Operating
Operativo	Operative
Oponente	Opposing
Oportunamente	Opportunely
Oportunista	Opportunist
Oportuno	Opportune
Opresivo	Oppressive
Opresor	Oppressive
Optativo	Optional
Óptimamente	Ideally
Óptimo	Ideal

Ej: El equipo de trabajo logró un rendimiento óptimo durante el proyecto, alcanzando todos los objetivos establecidos.

Ex: The work team achieved optimal performance during the project, reaching all the established goals.

Opuesto	Opposite
Opulento	Luxurious
Opusino	Sanctimonious
Oral	Oral
Ordenado	Tidy
Ordinal	Ordinal
Ordinario	Ordinary
Orgánico	Organic
Organizador	Organizing
Orgulloso	Proud
Oriental	Oriental
Orientativo	Guiding, illustrative
Original	Original
Originario	Original
Oriundo	Indigenous to

Ej: El famoso escritor Gabriel García Márquez, oriundo de Colombia, dejó un legado literario impresionante con sus obras maestras como “Cien años de soledad”.

Ex: The renowned writer Gabriel García Márquez, originally from Colombia, left an impressive literary legacy with his masterpieces like “One Hundred Years of Solitude.”

Ornamental	Ornamental
Orondo	Potbellied
Orquestal	Orchestral
Ortodoxo	Orthodox
Ortográfico	Spelling
Osado	Daring, bold
Oscuro	Dark
Óseo	Bony
Ostentoso	Ostentatious
Otoñal	Autumnal

Otro	Another
Ovalado	Oval
Oxigenado	Oxygenated

Spanish Verbs That Start With O

Spanish	English
Obcecarse	To become obsessed
Obedecer	To obey
Objetar	To object
Obligar	To force
Obrar	To act, to work, to be in one’s possession

Ej: El detective utilizó las pruebas encontradas para obrar en contra del sospechoso y resolver el caso.

Ex: The detective used the evidence found to act against the suspect and solve the case.

Observar	To observe
Obsesionar	To haunt, obsess
Obstaculizar	To hinder
Obstinarse	To dig one’s heels in, persist in doing something
Obstruir	To obstruct
Obtener	To obtain, win
Ocasionar	To cause

Ej: El accidente de tráfico ocasionó daños materiales en varios vehículos.

Ex: The car accident caused property damage to several vehicles.

Ocultar	To hide
Ocupar	To take up, to hold, to fill
Ocurrir	To happen
Odiar	To hate
Ofender	To offend
Ofertar	To offer
Oficiar	To conduct
Ofrecer	To offer
Ofrecerse	To offer itself
Ofuscar	To dazzle, bewilder
Oír	To hear

Ej: Me encanta oír el sonido de las olas del mar mientras paseo por la playa.

Ex: I love hearing the sound of the ocean waves while I walk along the beach.

Oler	To smell
Olfatear	To smell, to sniff
Olisquear	To smell, to sniff gently
Olvidar	To forget
Omitir	To leave out
Ondear	To wave, to ripple
Ondular	To wave
Opacar	To make opaque
Operar	To produce, operate
Opinar	To think

Ej: Me gustaría opinar sobre el tema de la educación pública y la necesidad de invertir más recursos en ella para mejorar la calidad de la enseñanza.

Ex: I would like to express my opinion on the topic of public education and the need to invest more resources in order to improve the quality of teaching.

Oprimir	To exert pressure on
Optar	To choose, decide
Orar	To pray
Ordenar	To arrange, tidy
Oredeñar	To milk
Orear	To air, get fresh air
Organizar	To organize
Oritentar	To position, direct
Originar	To cause

Ej: El mal tiempo puede originar retrasos en los vuelos.

Ex: Bad weather can cause delays in flights.

Orillar	To skirt, go around
Orinar	To urinate
Orquestrar	To orchestrate
Osar	To dare
Oscilar	To swing, oscillate
Oscurecer	To get dark
Ostentar	To show, flaunt
Otear	To scan
Otorgar	To grant
Ovacionar	To cheer, applaud
Ovillar	To wind, wind into a ball
Avular	To ovulate
Oxidar	To rust
Oxigenar	To oxygenate

I hope you found plenty of Spanish words that start with the letter O to add to your vocabulary bank. Let me know what your favorite Spanish words that start with O are in the comment below. For more vocabulary words, check out the following Spanish resources:

Are you a Spanish teacher teaching the letters to your students? Check out some of our free letter printables for a fun way to learn the letters.