Spanish words starting with O:

Full list of Spanish words that start with the letter O according to the Spanish dictionary. Search and filter them as you like. Find the translation in English behind the Spanish word.

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Spanish word	meaning in English	features
ó	or (once used instead of o near numerals to avoid confusion with a zero: 2 ó 3)	{conj}
-ó	A suffix indicating the third-person singular indicative preterite of a verb	{suffix}
óleo	oil	{m}
ómicron	omicron; the Greek letter Ο, ο	{f}
ómnibus	public bus	{m}
-ón	ending of every chemical element belonging only to the noble gases group, except helium (in spanish helio)	{suffix} [chemistry]
-ón	emphasizes contempt for subject	{suffix}
-ón	emphasizes that something is large, grand, intense, important	{suffix}
-ón	for few cases, indicates that something is used wrong or frequently (forming adjectives and or nouns)	{suffix}
-ón	forms a noun from a different (usually larger) but related or similar one	{suffix}
-ón	for very few cases, indicates small size of or a lack of something (such as an ironic augmentative)	{suffix}
-ón	indicates that someone or something has large attributes, or larger than usual	{suffix}
-ón	ending of most or every subatomic particle	{suffix} [nuclear physics]
-ón	suffixed to verbs, doing something repeatedly or often	{suffix}
ónfalos	omphalos	{m}
-ónimo	-onym	{suffix}
ónix	onyx	{m}
o	either ... or	{conj}
o	or	{conj}
o	Name of the letter O	{f}
o	The 16th letter of the Spanish alphabet	{letter}
-o	Suffix indicating the first-person singular present indicative of verbs	{suffix}
O	The 16th letter of the Spanish alphabet	{letter}
OA	Oaxaca (Mexican state)	{abbr}
Oaxaca	A state of Mexico	{prop}
oaxaqueño	Of or pertaining to the Mexican state of Oaxaca	{adj}
obcecado	stubborn, obsessed	{adj}
obedecer	to be because of	{v}
obedecer	to obey	{v}
obediencia	obedience	{f}
obediente	obedient	{adj}
obelisco	obelisk	{m}
obesa	An obese woman	{f}
obesidad	obesity (state of being obese)	{f}
obeso	obese	{adj}
obeso	An obese person	{m}
obispado	bishopric	{m}
obispal	episcopal	{adj}
obispo	bishop	{m}
obituario	obituary	{m}
objeción	objection	{f}
objetar	to object	{v}
objetivamente	objectively	{adv}
objetividad	objectivity	{f}
objetivo	objective	{adj}
objetivo	aim	{m}
objeto	object	{m}
objetor	conscientious objector	{m}
objetor	objector	{m}
objetor de conciencia	conscientious objector	{m}
objeto volador no identificado	unidentified flying object (all senses)	{m}
oíble	audible	{adj}
oblea	wafer (biscuit or in electronics)	{f}
obligación	obligation	{f}
obligado	coerced, forced	{adj}
obligado	committed	{adj}
obligar	to oblige, force, obligate	{v}
obligatorio	mandatory	{adj}
obligatorio	obligatory	{adj}
obliterar	to obliterate, to null, to erase	{v}
oblongo	oblong	{adj}
obnubilar	to daze	{v}
oboe	oboe	{m} [musical instruments]
obra	construction	{f}
obra	work, usually literary or artistic	{f}
obra de arte	work of art, objet d'art	{f}
obrar	to produce	{v}
obrera	feminine form of obrero	{f}
obrero	worker	{m}
obscenidad	obscenity	{f}
obsceno	obscene	{adj}
obscuro	obscure, dark	{adj}
obsequiar	to present	{v}
obsequioso	obsequious	{m}
observación	observation	{f}
observador	observant	{adj}
observador	observing	{adj}
observador	observer	{m}
observadora	feminine form of observador	{f}
observar	to observe	{v}
observatorio	observatory	{m}
obsesión	obsession	{f}
obsesionado	obsessed	{adj}
obsesionado	possessed	{adj}
obsesionar	to obsess	{v}
obsesiva	feminine form of obsesivo	{adj}
obsesivo	obsessive	{adj}
obsidiana	obsidian	{f}
obsolescente	obsolescent	{adj}
obsoleto	obsolete, outdated	{adj}
obstante	hindering	{adj}
obstante	obstructing	{adj}
obstar	to hinder	{v}
obstáculo	obstacle	{m}
obstetricia	obstetrics	{f}
obstinación	obstinacy	{f}
obstinado	stubborn	{adj}
obstinar	to be obstinate	{v}
obstrucción	obstruction	{f}
obstruir	to obstruct	{v}
obtener	to obtain	{v}
obtuso	obtuse	{adj} [geometry]
obtuso	obtuse (blunt)	{adj}
obtuso	obtuse (intellectually dull)	{adj}
obviamente	obviously	{adv}
obviar	to avoid	{v}
obviar	to obviate	{v}
obvio	obvious, clear	{adj}
oca	goose	{f}
océano	ocean	{m}
océano Atlántico	Atlantic Ocean (the ocean lying between the Americas to the west and Europe and Africa to the east)	{prop}
Océano Índico	Indian Ocean	{prop}
Océano Pacífico	Pacific Ocean	{prop}
ocarina	ocarina	{f}
ocasión	occasion	{f}
ocasional	occasional	{adj}
ocasionalmente	occasionally	{adv}
ocasionar	to cause	{v}
ocaso	west	{m} [geography]
ocaso	decline	{m} [literary]
ocaso	sunset	{m}
occidental	western	{adj}
occidentalización	westernization	{f}
occidentalizar	to westernize	{v}
occidente	west, occident	{m}
occiduo	Western, occidental	{adj} [poetic, literary]
occipital	occipital	{adj} [anatomy]
occipital	(muscle) occipitalis	{m}
occipital	occipital bone	{m}
occipital	occipital lobe	{m}
occipitofrontal	occipitofrontal	{adj} [anatomy]
occipitofrontal	occipitofrontalis, occipitofrontalis muscle	{m}
occitano	Of or relating to Occitania or the Occitan language	{adj}
occitano	Person from or inhabitant of Occitania	{m}
occitano	Occitan (the Romance language)	{prop}
Oceanía	Oceania	{prop}
oceanógrafo	oceanographer	{m}
oceanográfico	oceanographic	{adj}
ocelote	ocelot	{m}
oceánico	oceanic	{adj}
ochenta	eighty	{cardinal num} [cardinal]
ochenta y cinco	eighty-five	{num}
ocho	eight	{cardinal num} [cardinal]
Ochoa	Spanish surname	{prop}
ochocientas	feminine form of ochocientos	{num}
ochocientos	eight hundred	{num}
ocio	diversion	{m}
ocio	leisure, recreation, spare time	{m}
ociosidad	idleness, inactivity	{f}
ocioso	idle	{adj}
ocioso	idler	{m}
oclocracia	ochlocracy	{f}
oclocrático	ochlocratic	{adj}
ocote	Any of several aromatic, resinous pine species native to Mexico and Central America, especially the Montezuma pine (Pinus montezumae)	{m} [El Salvador, Guatemala, Honduras, Mexico, Nicaragua]
ocotillo	ocotillo	{m} [Mexico]
ocra	okra	{m} [El Salvador]
ocre	ochre	{m}
octagonal	octagonal	{adj}
octanaje	octane rating	{m}
octano	octane	{m} [organic compound]
octava	octave	{f} [music]
Octavio	male given name	{prop}
octavo	eighth	{adj}
octavo	eighth	{m}
octeto	octet	{m}
octágono	octagon	{m} [geometry]
octingentésimo	eight hundredth	{adj}
octodecágono	octadecagon	{m} [geometry]
octogenario	octogenarian	{adj}
octogenario	octogenarian	{m}
octogésimo	eightieth	{adj} [ordinal]
octogésimo	eightieth	{m}
octópodo	octopod (eight-legged)	{adj}
octópodo	octopod	{m}
octubre	October	{m}
ocular	ocular	{adj}
ocular	eyepiece, eyeglass	{m}
ocularmente	ocularly, visually, through the use of sight	{adv}
ocultación	occultation	{f}
ocultar	to hide	{v}
ocultarse	to be hidden	{v}
ocultarse	to hide	{v}
oculto	occult	{adj}
ocupación	occupation (all senses)	{f}
ocupacional	occupational	{adj}
ocupado	busy	{adj}
ocupado	occupied	{adj}
ocupante	occupying	{adj}
ocupante	occupant	{mf}
ocupar	to go about	{vr}
ocupar	to pay attention to	{vr}
ocupar	to employ	{v}
ocupar	to occupy	{v}
ocupar	to use	{v}
ocurrencia	occurrence	{f}
ocurrente	occurrent	{adj}
ocurrente	saying, meaning, showing or doing unexpected things	{adj}
ocurrir	to happen, to occur	{v}
oda	ode	{f}
odiar	to hate	{v}
odio	hate	{m}
odioso	hateful, odious	{adj}
odisea	odyssey	{f}
oído	ear (Specially the inner part of this)	{m}
oído	hearing	{m}
odontalgia	toothache	{f} [medicine]
odontólogo	odontologist; dentist	{m}
odontología	odontology; dentistry	{f}
odorífero	odorous, odoriferous	{adj}
odorífero	smelly	{adj}
odre	goatskin, goatskin wine bag	{m}
OEA	Organización de los Estados Americanos: OAS	{initialism}
oeste	west	{m}
Ofelia	female given name, equivalent to Ophelia	{prop}
ofenda	insult	{f}
ofender	to offend	{v}
ofendido	aggrieved	{adj}
ofensa	insult	{f}
ofensa	offense	{f}
ofensiva	offensive	{f}
ofensivo	offensive	{adj}
oferta	offer	{f}
ofertar	to offer	{v}
oficial	official	{adj}
oficial	artisan	{mf}
oficial	butcher	{mf}
oficial	clerk, functionary	{mf}
oficial	executioner	{mf}
oficial	officer, official	{mf}
oficial	office worker, skilled workman	{mf}
oficialidad	officiality	{f}
oficialismo	ruling party	{m}
oficializar	to make official	{v}
oficialmente	officially	{adv}
oficiar	to officiate	{v}
oficina	laboratory	{f}
oficina	office	{f}
oficina	workshop	{f}
oficinista	office worker	{mf}
oficio	profession, occupation	{m}
ofidio	ophidian	{adj}
ofidio	ophidian	{m}
ofrecer	to offer	{v}
ofrecido	easy (A person who readily consents to sexual activity)	{adj}
ofrecimiento	offering, offer	{m}
ofrenda	offering, sacrifice	{f}
ofrendar	to offer as a gift, to sacrifice	{v}
oftalmóloga	(female) ophthalmologist	{f}
oftalmólogo	ophthalmologist	{m}
oftalmología	opthalmology	{f}
oftalmoscopio	ophthalmoscope	{m}
ofuscación	bewilderment, confusion	{f}
ofuscación	blurring	{f}
ofuscación	obfuscation (lack of clarity)	{f}
ofuscar	to confuse	{v}
ofuscar	to obfuscate	{v}
ogro	crank	{m}
ogro	fiend, brute	{m}
ogro	ogre	{m}
oh	oh (expression of awe, surprise, pain or realization)	{interj}
oh, Dios mío	oh my God	{phrase}
Ohio	Ohio	{prop}
ohmio	ohm	{m}
-oide	-oid	{suffix}
oidor	judge, magistrate for a royal audiency	{m} [archaic]
oidor	hearer	{m}
ojalá	hopefully (I hope that)	{adv}
ojalá	God grant (that) (followed by present subjunctive)	{interj}
ojalá	God willing	{interj}
ojalá	I hope so; let’s hope so	{interj}
ojalá	I hope (that); let’s hope (that) (followed by present subjunctive)	{interj}
ojalá	I wish (when used to refer to past events)	{interj}
ojalá	Let's hope that	{interj}
ojal	buttonhole	{m}
ojal	loop	{m}
ojeada	glance (brief look)	{f}
ojear	to ogle	{v}
ojear	to put the evil eye (on somebody), to curse by looking with malicious intents	{v}
ojera	coon eyes	{f}
ojete	anal orifice	{m} [Argentina]
ojete	anus	{m} [colloquial]
ojete	eye hole	{m}
ojete	eyelet	{m}
ojete	wicked, mean, bad person	{m} [Mexico]
ojete	asshole	{m} [slang as epithet]
ojialegre	laughing-eyed	{adj}
ojimoreno	dark-eyed, brown-eyed	{adj}
ojinegro	dark-eyed, black-eyed	{adj}
ojito	diminutive form of ojo	{m}
ojituerto	cross-eyed, cock-eyed	{adj}
ojiva	ogive	{f}
ojiva	warhead	{f}
ojón	Having big or very open eyes	{adj}
ojón	A particular fish, having very large eyes	{m}
ojón	Someone with big or very open eyes	{m}
ojo	look! watch out!	{interj}
ojo	eye	{m}
ojo de agua	spring	{m}
ojota	flip-flop (artisanal type)	{f} [Chile, Argentina, Peru]
Oklahoma	Oklahoma	{prop}
okupa	squatter; squat	{mf} [slang, Spain]
okupación	squatting	{f} [slang, Spain]
okupado	squatted	{adj} [slang, Spain]
okupar	to squat	{v} [slang, Spain]
olé	An expression of encouragement and approval	{interj}
ola	sudden appearance of a large amount of something	{f} [figuratively]
ola	wave (on the surface of a liquid)	{f}
ola de calor	heat wave, hot spell	{f}
olalia	olallieberry	{f}
olíbano	frankincense	{m}
oleada	wave	{f}
oleaje	surf	{m} [hydrography]
oleato	oleate	{m}
oleico	oleic	{adj}
oleoducto	oil pipeline	{m}
oleoplasto	oleoplast	{m} [cytology]
oler	to smell, to emit an odour	{vi}
oler	to smell, to perceive by scent	{vt}
olerse la tostada	to smell a rat	{v} [idiomatic]
oleuropeína	oleuropein	{f} [organic compound]
oleyliberi	olallieberry	{f}
olfatear	to sniff	{v}
olfativo	olfactory	{adj}
olfato	smell, olfaction, sense of smell (sense that detects smells)	{m}
olfatorio	olfactory	{adj}
Olga	female given name	{prop}
oligarquía	oligarchy	{f}
oligonucleótido	oligonucleotide	{m} [biochemistry]
oligosacárido	oligosaccharide	{m} [carbohydrates]
olimpíada	olympiad	{f}
olimpíada	Olympics	{f}
olimpiada	olympiad	{f}
olio	see óleo	{m}
olisquear	to sniff at	{v}
oliva	olive (fruit)	{f} [context needed, comment=where is this used vs. aceituna?]
olivar	olive color	{adj}
olivar	olive grove	{m}
olivino	olivine (family of minerals)	{m}
olivo	olive tree	{m}
olla	a pool, a whirlpool	{f}
olla	a pot or pan; a kettle	{f}
olla	a stew	{f}
olmeca	Olmec	{adj}
olmeca	Olmec	{mf}
olmo	elm	{m}
olímpico	olympic	{adj}
olímpico	Olympian	{m}
olor	smell, scent	{m}
oloroso	odorous	{adj}
oloroso	sweet (having a pleasant smell)	{adj}
olote	corncob	{m} [Central America, Mexico]
Oltenia	Oltenia	{prop}
olvidadizo	forgetful	{adj}
olvidado	forgotten	{adj}
olvidar	to forget	{v}
olvido	forgetting, ending of memory	{m}
olvido	Idea meaning an abstract place to put what is wanted to be forgotten	{m}
olvido	oblivion	{m}
-oma	-oma	{suffix} [pathology]
omaní	Omani	{adj}
omaní	Omani	{mf}
Omar	male given name	{prop}
ombú	A large evergreen tree native to the Pampa of South America, Phytolacca dioica	{m}
ombligo	navel (remnant of umbilical cord)	{m}
ombre	obsolete spelling of hombre	{m}
OMC	initialism of Organización Mundial de Comercio (WTO (World Trade Organisation))	{initialism}
omega	omega; the Greek letter Ω, ω	{f}
ominar	to omen	{v}
omisión	omission	{f}
omiso	neglectful, careless	{adj}
omitir	to omit	{v}
Omán	Oman (country in the Middle East)	{prop}
omnipotencia	omnipotence (unlimited power)	{f}
omnipresencia	omnipresence	{f}
omnipresente	omnipresent	{adj}
omnisciencia	omniscience	{f}
omóplato	scapula	{m}
OMS	Organización Mundial de la Salud; WHO	{initialism}
-ona	feminine form of -ón	{suffix}
onagro	onager (military engine)	{m}
onagro	onager (wild ass)	{m}
once	eleven	{cardinal num} [cardinal]
once	snack (bread with tea or coffee)	{f} [Latin American Spanish]
oncólogo	oncologist (one who specialises in oncology)	{m}
oncología	oncology (branch of medicine)	{f}
onda	Any other wave (including technological use)	{f}
onda	style, fashion	{f} [Chile]
onda	vibe or mood	{f}
onda	wave (on the surface of a liquid)	{f}
onda acústica	sound wave	{f}
onda electromagnética	electromagnetic wave	{f}
onda senoidal	sine wave	{f} [trigonometry]
onda sonora	sound wave	{f}
onda verde	green wave	{f}
ondear	to undulate	{v}
ondular	to wave	{v}
ondulatorio	undulating	{adj}
ondulatorio	wave (attributive, physics)	{adj}
oneroso	onerous	{adj}
ONG	NGO (non-governmental organisation)	{initialism}
onomatopeya	onomatopoeia	{f}
onomatopéyico	onomatopoeic	{adj}
onírico	oneiric	{adj}
ontogenetica	feminine form of ontogenetico	{adj}
ontogenetico	ontogenetic, ontogenic	{adj} [biology]
ontogenia	ontogeny	{f}
ontología	ontology	{f}
ONU	initialism of Organización de las Naciones Unidas (UNO (United Nations Organization))	{initialism} [politics, government]
onza	ounce	{f}
onza	ounce; snow leopard	{f}
oolito	oolite	{m} [geology]
oolítico	oolitic	{adj} [geology]
ooteca	ootheca	{f}
opacidad	opacity	{f}
opción	option	{f}
opcional	optional	{adj}
open	open	{m} [sports]
O.P.E.P.	organización de los países exportadores de petróleo, OPEC	{acronym}
operación	operation	{f} [computing, mathematics]
operacional	operational, effective, operative	{adj}
operacional	working	{adj}
operador	operator	{m}
operadora	feminine form of operador, (female) operator	{f}
operar	to operate	{v}
operaria	working woman	{f}
operario	operative	{m}
operario	workman	{m}
operativo	operative	{adj}
operativo	operation	{m}
opereta	operetta	{f} [music]
opiáceo	opiate	{adj}
opimo	rich, fertile, lush	{adj}
opinar	to express one's opinion; to opine	{v}
opinar	to think; to be of the opinion	{v}
opinión	opinion	{f}
opio	opium	{m}
opioide	opioid	{adj}
opioide	opioid	{m}
oponente	opponent	{mf}
oponer	to be opposed, to be in opposition	{vr}
oponer	to pit (one thing against another); to set in opposition	{vt}
oponer	to put up (resistance etc.)	{vt}
oponerse	to oppose one another	{vr}
oporto	port wine	{m}
Oporto	Oporto	{prop}
oportunamente	opportunely, timely	{adv}
oportunidad	opportunity (in both senses: “chance for advancement, progress or profit” and “favorable circumstance or occasion”)	{f}
oportunismo	opportunism	{m}
oportunista	opportunist	{f}
oportuno	opportune	{adj}
oportuno	suitable, appropriate	{adj}
oposición	opposition	{f}
opositor	opponent	{m}
opresión	oppression	{f}
oprimir	to oppress	{v}
oprimir	to press (e.g., a button or key on a telephone or keyboard)	{v}
oprobio	opprobrium	{m}
ops	acknowledgment of a minor mistake, oops	{m}
opúsculo	opuscule, tract, short essay	{m}
opsonina	opsonin	{f} [biology]
optar	to opt	{v}
optimar	to optimize	{v}
optimismo	optimism	{m}
optimista	optimistic	{adj}
optimista	optimist	{mf}
optimizar	to optimize	{v}
optometría	optometry	{f}
opuesto	contrary	{adj}
opuesto	opposed	{adj}
opuesto	opposite	{adj}
opulencia	opulence	{f}
oquedad	hollow, hollow space, cavity, hole	{f}
oquedad	insubstantiality of speech or talk	{f}
oír	to hear	{vi}
oír	to hear	{vt}
oír	to heed; to listen to	{vt}
oír	to listen	{vt}
oración	clause	{f}
oración	oration	{f}
oración	prayer	{f}
oración	sentence	{f}
orador	orator	{m}
oradora	feminine form of orador	{f}
oral	oral	{adj}
oralidad	orality	{f}
oralmente	orally	{adv}
orangután	orangutan	{m}
orar	to pray	{v}
orate	A crazy person	{mf} [pejorative]
oratoria	oratory	{f}
orbe	globefish	{m}
orbe	mound (part of the regalia)	{m}
orbe	orb	{m}
orbe	world	{m}
orbicular de los párpados	orbicularis oculi, orbicularis oculi muscle	{m}
orbital	orbital	{adj}
orbitar	To orbit	{v}
orca	orca, killer whale	{f}
orco	male orca, killer whale	{m}
orco	orc	{m}
orco	Orcus	{m}
orco	hell	{m} [poetic]
oráculo	oracle	{m}
ordalía	ordeal, trial	{n}
ordeñar	to milk	{v}
orden	order (command)	{f}
orden	order (request, purchase, or food)	{f}
orden	order	{f} [religion]
orden	order	{m} [biology, classification]
orden	good behavior	{m}
orden	order (highest exponent)	{m} [mathematics]
orden	order (arrangement, sequence, organization)	{m}
orden	orderliness	{m}
ordenación	ordination	{f}
ordenada	ordinate	{f}
ordenado	ordered	{adj}
ordenador	computer	{m}
ordenanza	ordinance	{mf} [feminine only]
ordenanza	messenger	{mf}
ordenanza	orderly	{mf}
ordenar	to enjoin	{v}
ordenar	to order	{v}
ordenar	to sort	{v}
ordeño	milking	{m}
ordinal	ordinal	{adj}
ordinariamente	ordinarily	{adv}
ordinario	ordinary	{adj}
Ordoño	male given name	{prop}
orear	to air	{v}
Oregón	Oregon	{prop}
oreja	ear	{f}
oreja de mar	abalone (edible univalve mollusc)	{f}
orejera	blinder (for horses)	{f}
orejera	ear armour	{f}
orejera	earflap	{f}
orejera	earmuff	{f}
orejera	earpad	{f}
orejera	plug (jewellery for the ear)	{f}
orejuela	The earlike handle of a tray, bowl or other such utensil	{f}
orellano	remote, separated	{adj} [archaic]
oreo	breeze	{m}
oreo	fresh air	{m}
orfanato	orphanage	{m}
orfebre	goldsmith	{mf}
orfebrería	gold work, goldsmithing	{f}
orgía	orgy	{f}
organela	organelle	{f}
organelo	organelle	{m}
organigrama	organization chart	{f}
organillo	street organ	{m}
organismo	corporate body	{m}
organismo	human body	{m}
organismo	organism, creature	{m}
organismo	organization, committee, body	{m}
organista	organist	{mf}
organización	organization	{f}
organizacional	organizational	{adj}
organizado	organized	{adj}
organizador	organizer	{m}
organizar	to organize	{v}
organizativo	organizational	{adj}
orégano	oregano, pot marjoram (Origanum vulgare)	{m}
organoclorado	organochloride	{m}
organofosfato	organophosphate	{m}
organografía	organography	{f}
organometálico	organometallic	{adj}
orgasmo	orgasm	{m}
orgiástico	orgiastic	{adj}
orgánico	organic	{adj}
orgánulo	organelle	{m}
orgullo	pride	{m}
orgullosamente	proudly	{adv}
orgulloso	proud	{adj}
orientación	orientation	{f}
orientación familiar	home teaching	{f}
orientación sexual	sexual orientation	{f}
oriental	eastern	{adj}
oriental	Oriental	{adj}
orientar	to orient	{v}
oriente	east	{m}
Oriente Medio	Middle East (region comprising southwest Asia and northeast Africa)	{prop}
orificio	orifice	{m}
origen	origin	{m}
original	original	{adj}
originalmente	originally	{adv}
originar	to originate	{v}
originar	to give rise to, to cause	{vt}
originar	to start	{vt}
originario	native	{adj}
originario	original	{adj}
orilla	edge, border	{f}
orilla	shore or bank of a watercourse	{f}
orillar	to skirt	{v}
orillero	lower-class, common, vulgar	{adj}
Orión	Orion (constellation)	{prop}
Orión	Orion (in mythology)	{prop}
orina	urine	{f}
orinal	chamber pot	{m}
orinar	to urinate	{v}
Oriol	male given name	{prop}
oriundo	native to	{adj}
oriundo	native	{mf}
orlar	to add a border to	{v}
orlar	to trim	{v}
orín	rust (caused by moisture)	{m}
orín	urine	{m} [usually, plural]
ornamental	ornamental	{adj}
ornamentar	to adorn or ornament	{v}
ornamento	ornament	{m}
ornar	to adorn	{v}
ornitina	ornithine	{f} [amino acid]
ornitología	ornithology	{f}
ornitomancía	alternative spelling of ornitomancia	{f}
ornitomancia	ornithomancy	{f}
ornitorrinco	platypus	{m}
oro	gold	{m}
orografía	orography (all senses)	{f}
orográfico	orographic	{adj}
oropel	tinsel	{m}
oropimente	orpiment	{m} [mineralogy]
orozuz	licorice	{m} [plants]
orquídea	orchid	{f}
orquesta	orchestra	{f}
orquestal	orchestral	{adj}
orquestar	to orchestrate	{v}
orquestra	orchestra	{f}
orquidectomía	orchidectomy	{f} [surgery]
Ortega	Spanish surname	{prop}
ortógrafa	feminine form of ortógrafo	{f}
ortógrafo	orthographer	{m}
ortiga	nettle (plant)	{f}
Ortiz	Spanish surname	{prop}
orto	sundown	{m}
orto	arse, anus	{m} [vulgar, Argentina, Uruguay]
orto	anus	{m} [vulgar, Chile]
orto-	ortho-	{prefix}
ortobirrotonda	orthobirotunda	{f} [geometry]
ortodoncia	orthodontics	{f}
ortodoncista	orthodontist	{mf}
ortodoxia	orthodoxy (all senses)	{f}
ortodoxo	orthodox	{adj}
ortodoxo	Orthodox	{adj}
ortoedro	cuboid	{m} [geometry]
ortografía	orthography	{f}
ortografía	spelling (a person's ability to spell words)	{f}
ortografía	spelling (specific way of spelling a word)	{f}
ortográfico	orthographic	{adj}
ortopédica	feminine form of ortopédico	{f}
ortopédico	orthopedic	{adj}
ortopédico	orthopedist	{m}
ortopedia	orthopedics	{f} [medicine]
ortopedista	orthopedist	{mf}
oruga	arugula (plant)	{f}
oruga	caterpillar (insect or vehicle)	{f}
orureño	Of, from, or in the style of the Bolivian department (region) of Oruro	{adj}
orvallo	drizzle	{m} [Spain]
orzuelo	stye	{m}
os	you, to you, for you; dative and accusative of vos and vosotros	{pron}
osadía	audacity	{f}
osadía	boldness	{f}
osado	daring, bold	{adj}
osamenta	skeleton	{f}
osar	to dare	{vi}
osario	ossuary	{m}
oscilación	oscillation	{f}
oscilar	to oscillate	{v}
osciloscopio	oscilloscope	{m}
oscurecer	to darken	{v}
oscuridad	darkness, obscurity	{f}
oscuro	dark	{adj}
o sea	I mean; that is to say; used to introduce a new idea or explain a previous one	{adv} [informal]
osezno	bear cub	{m}
osicón	informer, tattler	{m}
osito	(a lovable man) teddy bear	{m}
osito	diminutive form of oso, little bear	{m}
osito de peluche	Teddy bear	{m}
osmio	osmium	{m}
oso	bear	{m}
oso	bear	{m} [slang]
-oso	-ous, -y	{suffix}
oso blanco	polar bear	{m}
oso de agua	A tardigrade, water bear	{m}
oso de anteojos	spectacled bear	{m}
oso hormiguero	anteater	{n}
oso hormiguero	An uncircumcised penis, a cheeser	{n}
oso Kodiak	Kodiak bear	{m}
oso lavador	raccoon	{m}
oso malayo	sun bear	{m}
oso negro	black bear	{m}
oso panda	panda; panda bear	{m}
oso pardo	brown bear (Ursus arctos)	{m}
oso polar	polar bear	{m}
oso tibetano	Asian black bear; moon bear	{m}
ostensible	ostensible, apparent	{adj}
ostensiblemente	ostensibly	{adv}
ostentación	conceit	{f}
ostentación	ostentation, boastfulness	{f}
ostentar	to display or flaunt	{v}
ostentoso	flashy; showy	{adj}
osteocondrosis	osteochondrosis	{f} [pathology]
osteofito	osteophyte	{m}
osteosíntesis	osteosynthesis	{f} [surgery]
ostia	oyster	{f}
ostión	oyster (particularily from genus Crassostrea), specially when prepared or served for food	{m} [Mexico]
ostomía	ostomy	{f} [surgery]
ostra	oyster	{f}
ostrogodo	Ostrogothic	{adj}
ostrogodo	Ostrogoth	{m}
Oswaldo	male given name	{prop}
-ota	feminine form of -ote	{suffix}
OTAN	NATO	{acronym}
-ote	emphasizes contempt for subject	{suffix}
-ote	emphasizes size	{suffix}
otear	to survey	{v}
otero	knoll	{m}
otoñal	autumnal	{adj}
otomí	Of or pertaining to the Otomi people and their language	{adj}
otomí	A member of the Otomi people	{mf}
otomí	the Otomi language	{prop}
otoño	autumn, fall	{m}
otoplastia	otoplasty	{f} [surgery]
otorgamiento	Act of granting or awarding	{m}
otorgar	to award	{v}
otorgar	to grant	{v}
otorrinolaringóloga	feminine form of otorrinolaringólogo	{f}
otorrinolaringólogo	otorhinolaryngologist	{m}
otorrinolaringología	otorhinolaryngology	{f}
otra	feminine of otro; another, another one	{pron}
otras	feminine plural of otro; other	{adj}
otra vez	again	{adv} [idiomatic]
otredad	otherness	{f} [philosophy]
otro	other, another	{adj}
otro	"Not again!" or "What, again?" (also Otra vez! or Otra vez?)	{interj}
ovación	ovation	{f}
ovacionar	to hail (praise enthusiastically)	{v}
oval	oval; shaped like an oval	{adj}
ovario	ovary	{m} [anatomy, botany]
oveja	sheep	{f}
oveja negra	black sheep	{f} [idiomatic]
ovejera	feminine form of ovejero	{f}
ovejero	shepherd	{m}
overol	overalls plural (not US), coveralls plural (US only)	{m}
ovetense	Oviedan	{adj}
ovetense	Oviedan	{mf}
oviedista	A person connecting with Real Oviedo, a Spanish football team from the city of Oviedo	{mf} [soccer]
Oviedo	Oviedo	{prop}
Oviedo	The letter O in the Spanish phonetic alphabet	{prop}
ovillar	To roll into a ball	{v}
OVNI	objeto volador no identificado; UFO	{abbr}
ovoalbúmina	ovalbumin	{f} [protein]
ovoide	ovoid (egg-shaped)	{adj}
ovoide	ovoid	{m}
ovíparo	oviparous	{adj}
ovular	to ovulate	{v}
oxalato	oxalate	{m} [organic compound]
oxaloacetato	oxaloacetate	{m} [organic compound]
oxaloacético	oxaloacetic	{adj}
oxalocrotonato	oxalocrotonate	{m} [chemistry]
oxazol	oxazole	{m} [organic compound]
oxácido	oxyacid	{m}
oxígeno	oxygen	{m}
oxhídrico	oxyhydrogen	{adj} [chemistry]
oxhidrilo	hydroxyl	{m} [chemistry]
oxidable	oxidizable	{adj}
oxidación	oxidation	{f}
oxidante	oxidizing	{adj} [chemistry]
oxidante	oxidizing agent, oxidant	{m} [chemistry]
oxidar	to oxidize	{v}
oxidasa	oxidase	{f} [enzyme]
oxidativo	oxidative	{adj}
oxidorreductasa	oxidoreductase	{f} [enzyme]
oxigenación	oxygenation	{f}
oxigenar	to oxygenate	{v}
oxigenasa	oxygenase	{f} [enzyme]
oxihemoglobina	oxyhemoglobin	{f}
oximetría	oximetry	{f}
oxitocina	oxytocin	{f} [hormone]
oxálico	oxalic	{adj}
oxímoron	oxymoron (figure of speech)	{m}
oxonio	oxonium	{m} [chemistry]
oyamel	sacred fir (Abies religiosa)	{m}
oye	(exclamation) hey	{interj}
ozono	ozone	{m}
ópalo	opal	{m}
ópera	opera	{f} [music]
óptica	feminine form of óptico	{adj}
ópticas	feminine plural of óptico	{adj}
óptico	optical; optic	{adj}
ópticos		{adj} [masculine plural of, óptico]
óptimo	optimal	{adj}
óptimo	superlative form of bueno, very good	{adj}
órale	let's go, come on, hurry (used to exhort)	{interj} [Mexico]
órale	oh my God, wow (indicates amazement, astonishment, excitement, surprise, shock, fear)	{interj} [Mexico]
órale	yes, ok (indicates approbation)	{interj} [Mexico]
órbita	orbit	{f}
órdago	a large bet; an all-or-nothing bet	{m}
órgano	organ (all senses)	{m}
Óscar	male given name	{prop}
ósculo	kiss	{m} [formal]
óseo	osseous, bony	{adj}
ósmosis	osmosis	{f}
ósmosis	osmosis	{f} [slang]
óvalo	oval	{m}
óvulo	ovum, egg	{m}
óxido	oxide	{m}
óxido	rust	{m}
óxido de calcio	calcium oxide	{m}