Words That Start with O (1000+ O Words in English)

This reference is designed to teach English learners about words that start with O. You’ll find sections covering various categories like positive words, descriptive words, adjectives, and verbs. It also includes examples and meanings of common and unique words. The aim is to enrich your vocabulary and help you better understand how to use these words in different contexts.

Words that Start with O

Words that Start with O
Words that Start with O – Created by 7ESL

Positive Words that Start with O

  • Oasis
  • Oath
  • Obedient
  • Objective
  • Oblige
  • Obliging
  • Observable
  • Observant
  • Obtain
  • Occasion
  • Odyssey
  • Offering
  • Ok
  • Olympian
  • Omnipotent
  • Omniscient
  • Ongoing
  • Onset
  • Onward
  • Open
  • Open-minded
  • Operable
  • Opportune
  • Opportunity
  • Optimism
  • Optimum
  • Option
  • Opulent
  • Orchestrate
  • Ordain
  • Order
  • Orderly
  • Organic
  • Orgasm
  • Oriented
  • Original
  • Originate
  • Ornamental
  • Ornate
  • Outclass
  • Outdo
  • Outperform
  • Outrank
  • Outreach
  • Outshine
  • Outsmart
  • Outstanding
  • Ovation
  • Overjoyed
  • Overtake

Explore more: Words that start with O that are positive

Descriptive Words that Start with O

  • Oafish
  • Obdurate
  • Obedient
  • Obeisant
  • Obese
  • Objectionable
  • Objective
  • Obligated
  • Oblong
  • Obsolete
  • Obtainable
  • Obtuse
  • Obvious
  • Occasional
  • Oceanic
  • Octagonal
  • Octogenarian
  • Ocular
  • Odd
  • Odious
  • Offbeat
  • Offense
  • Offensive
  • Official
  • Oily
  • Old
  • Olive
  • Olympic
  • One
  • Only
  • Opaque
  • Open
  • Operatic
  • Operating
  • Operative
  • Opportune
  • Opposite
  • Orange
  • Organic
  • Ornate
  • Other
  • Outbound
  • Outdated
  • Outer
  • Outermost
  • Outgoing
  • Outrageous
  • Outside
  • Outspoken
  • Overt

Related: Descriptive Words

Adjectives that Start with O

  • Oaken
  • Oaten
  • Obedient
  • Obese
  • Objectionable
  • Oblate
  • Obligate
  • Obligational
  • Obligatory
  • Obliging
  • Oblique
  • Obliterable
  • Obliterated
  • Oblong
  • Obscene
  • Obscure
  • Observable
  • Observant
  • Obsolete
  • Occasional
  • Occult
  • Occupied
  • Oceanic
  • Ocular
  • Odd
  • Oddest
  • Odorless
  • Off
  • Offbeat
  • Offensive
  • Offside
  • Oily
  • Olden
  • Olfactory
  • Olive
  • Omissive
  • Omnibus
  • One
  • Ongoing
  • Only
  • Open
  • Opened
  • Operable
  • Opportune
  • Opposed
  • Opposite
  • Original
  • Orthodox
  • Outrageous
  • Outstanding

Learn more: Adjectives that start with O

Words that Start with O that are Used to Describe Someone

  • Oafish
  • Obedient
  • Objectionable
  • Obliging
  • Oblivious
  • Obnoxious
  • Obsessive
  • Obstructive
  • Occupied
  • Odd
  • Odious
  • Offbeat
  • Offensive
  • Old
  • Older
  • Oldest
  • One
  • One-sided
  • Open
  • Opinionated
  • Oppressive
  • Optimal
  • Optimistic
  • Orderly
  • Ordinary
  • Organized
  • Orphaned
  • Otherwise
  • Our
  • Outgoing
  • Outlandish
  • Outmoded
  • Outraged
  • Outrageous
  • Outspoken
  • Outstanding
  • Overactive
  • Overage
  • Overbearing
  • Overcautious
  • Overjoyed
  • Overrated
  • Overt
  • Overweight
  • Overwhelmed
  • Overwhelming
  • Overworked
  • Overwrought
  • Overzealous
  • Own

Discover more: O Words to Describe Someone

Nouns that Start with O

  • Oaf
  • Oak
  • Oar
  • Oatmeal
  • Obituary
  • Object
  • Objection
  • Occasion
  • Occult
  • Occupation
  • Ocean
  • Octopus
  • Odometer
  • Odor
  • Odyssey
  • Offender
  • Offer
  • Office
  • Officer
  • Official
  • Offshoot
  • Oil
  • Olive
  • Omen
  • One
  • Onion
  • Opal
  • Opening
  • Opera
  • Operator
  • Orb
  • Orbit
  • Otter
  • Outbreak
  • Outcast
  • Outcome
  • Outcry
  • Outdoors
  • Outfield
  • Outhouse
  • Oval
  • Ovation
  • Oven
  • Over
  • Overall
  • Overcoat
  • Owl
  • Owner
  • Ox
  • Oyster

Learn more: Nouns that start with O

Verbs that start with O

  • Obey
  • Object
  • Obligate
  • Oblige
  • Obscure
  • Observe
  • Obsess
  • Obstruct
  • Obtain
  • Occlude
  • Occupy
  • Occur
  • Offend
  • Offer
  • Officiate
  • Ogle
  • Ogle
  • Omit
  • Ooze
  • Open
  • Operate
  • Oppose
  • Oppress
  • Opt
  • Optimize
  • Orbit
  • Orchestrate
  • Ordain
  • Order
  • Organize
  • Orientate
  • Oust
  • Outgrow
  • Outlaw
  • Outline
  • Outsmart
  • Outsource
  • Overburden
  • Overcome
  • Overcook
  • Overdo
  • Overdraw
  • Overflow
  • Overhaul
  • Overload
  • Overpower
  • Oversee
  • Owe
  • Own

Find out more: Verbs that start with O

Common Words that Start with O with Examples

Words Example Sentences
Obedient The dog was obedient and always followed its owner’s commands.
Obese The doctor warned the patient that they were at risk for health problems due to being obese.
Objective The news article was written with an objective point of view, presenting all sides of the story.
Obligation It is my obligation to attend my sister’s wedding, even though I have a lot of work to do.
Obscure The meaning of the ancient text was obscure, and scholars struggled to decipher it.
Obsess My friend is obsessed with collecting antique dolls and has a whole room dedicated to them.
Obsolete The old computer was obsolete and could no longer run the latest software.
Obstruct The fallen tree obstructed the road and prevented traffic from passing through.
Obtain I need to obtain a copy of my birth certificate for my passport application.
Obvious It was obvious that the politician was lying, as their story kept changing.

Unique Words that Start with O with Meanings

Words Meanings
Oasis A fertile spot in a desert, where water is found
Obfuscate To make something unclear or difficult to understand
Oblivion The state of being completely forgotten or unknown
Obsequious Overly eager to please or obey
Odious Extremely unpleasant or repulsive
Officious Overly eager in offering unwanted advice or services
Ogle To stare at someone or something in a lewd or desirous manner
Ominous Giving the impression that something bad or unpleasant is going to happen
Opaque Not able to be seen through; not transparent
Opulent Rich and luxurious
Ornate Elaborately decorated
Ostentatious Showy, in an attempt to impress others
Ostracize To exclude someone from a society or group
Overwrought In a state of emotional turmoil; excessively nervous or excited
O Words
O Words – Created by 7ESL

List of Words that Start with O

Words that Start with Oa

  • Oafish
  • Oak
  • Oaken
  • Oaks
  • Oakum
  • Oar
  • Oars
  • Oarsman
  • Oarsmen
  • Oases
  • Oasis
  • Oat
  • Oaten
  • Oath
  • Oaths
  • Oatmeal
  • Oats

Words that Start with Ob

  • Obduracy
  • Obdurate
  • Obedience
  • Obedient
  • Obediently
  • Obeisance
  • Obeisant
  • Obelisk
  • Obelisks
  • Oberlin
  • Oberon
  • Obese
  • Obesity
  • Obey
  • Obeyed
  • Obeying
  • Obeys
  • Obituary
  • Object
  • Objected
  • Objecting
  • Objection
  • Objectionable
  • Objections
  • Objective
  • Objectively
  • Objectives
  • Objector
  • Objectors
  • Objects
  • Oblate
  • Oblation
  • Oblations
  • Obligate
  • Obligated
  • Obligation
  • Obligational
  • Obligations
  • Obligatory
  • Oblige
  • Obliged
  • Obliges
  • Obliging
  • Obligingly
  • Oblique
  • Obliquely
  • Obliquity
  • Obliterable
  • Obliterate
  • Obliterated
  • Obliterating
  • Obliteration
  • Oblivion
  • Oblivious
  • Oblong
  • Obloquy
  • Obnoxious
  • Obscene
  • Obscenity
  • Obscura
  • Obscure
  • Obscured
  • Obscurely
  • Obscures
  • Obscuring
  • Obscurities
  • Obscurity
  • Obsequies
  • Obsequious
  • Obsequiously
  • Obsequiousness
  • Observable
  • Observance
  • Observances
  • Observant
  • Observation
  • Observations
  • Observatories
  • Observatory
  • Observe
  • Observed
  • Observer
  • Observers
  • Observes
  • Observing
  • Obsess
  • Obsessed
  • Obsession
  • Obsessive
  • Obsidian
  • Obsolete
  • Obstacle
  • Obstacles
  • Obstante
  • Obstinacy
  • Obstinate
  • Obstinately
  • Obstreperous
  • Obstruct
  • Obstructed
  • Obstructing
  • Obstruction
  • Obstructions
  • Obstructive
  • Obstructs
  • Obtain
  • Obtainable
  • Obtained
  • Obtaining
  • Obtains
  • Obtrude
  • Obtruded
  • Obtruding
  • Obtrusive
  • Obtuse
  • Obtuseness
  • Obverse
  • Obviate
  • Obviated
  • Obvious
  • Obviously

Words that Start with Oc

  • Occasion
  • Occasional
  • Occasionally
  • Occasioned
  • Occasioning
  • Occasions
  • Occlude
  • Occult
  • Occupancy
  • Occupant
  • Occupants
  • Occupation
  • Occupational
  • Occupations
  • Occupied
  • Occupier
  • Occupiers
  • Occupies
  • Occupy
  • Occupying
  • Occur
  • Occurred
  • Occurrence
  • Occurrences
  • Occurring
  • Occurs
  • Ocean
  • Oceanic
  • Oceans
  • Ochre
  • Oct
  • Octagon
  • Octagonal
  • Octavo
  • October
  • Octogenarian
  • Octopus
  • Ocular
  • Oculist

Words that Start with Od

  • Odd
  • Odder
  • Oddest
  • Oddities
  • Oddity
  • Oddly
  • Odds
  • Odes
  • Odious
  • Odium
  • Odometer
  • Odor
  • Odoriferous
  • Odorless
  • Odorous
  • Odors
  • Odyssey

Words that Start with Oe, Of

  • Oeuvre
  • Oeuvres
  • Of
  • Off
  • Offal
  • Offbeat
  • Offence
  • Offences
  • Offend
  • Offended
  • Offender
  • Offenders
  • Offending
  • Offends
  • Offense
  • Offenses
  • Offensive
  • Offensively
  • Offer
  • Offered
  • Offering
  • Offerings
  • Offers
  • Offhand
  • Office
  • Officer
  • Officered
  • Officers
  • Offices
  • Official
  • Officially
  • Officials
  • Officiate
  • Officiated
  • Officiating
  • Officinalis
  • Officio
  • Officious
  • Officiously
  • Officiousness
  • Offing
  • Offset
  • Offshoot
  • Offshoots
  • Offshore
  • Offside
  • Offspring
  • Often
  • Oftener
  • Oftenest
  • Oftentimes
  • Ofttimes

Words that Start with Og, Oh, Oi, Ok

  • Ogden
  • Ogier
  • Ogilvie
  • Ogilvy
  • Ogle
  • Oglethorpe
  • Ogling
  • Oh
  • Oil
  • Oilcloth
  • Oiled
  • Oiling
  • Oils
  • Oilskin
  • Oilskins
  • Oily
  • Ointment
  • Ointments
  • Ok

Words that Start with Ol

  • Old
  • Olden
  • Older
  • Oldest
  • Oldfield
  • Oldham
  • Oleanders
  • Olfactory
  • Olga
  • Oligarchical
  • Oligarchy
  • Oliphant
  • Olive
  • Oliver
  • Olives
  • Olivet
  • Olivia
  • Olivier
  • Olla
  • Olly
  • Olney
  • Olof
  • Olsen
  • Olson
  • Olympia
  • Olympian
  • Olympic
  • Olympus

Words that Start with Om

  • Omaha
  • Ombre
  • Ombres
  • Omega
  • Omelet
  • Omen
  • Omens
  • Omer
  • Ominous
  • Ominously
  • Omission
  • Omissions
  • Omissive
  • Omit
  • Omits
  • Omitted
  • Omitting
  • Omni
  • Omnia
  • Omnibus
  • Omnibuses
  • Omnipotence
  • Omnipotent
  • Omnipresent
  • Omniscience
  • Omniscient
  • Omnium
  • Omnivorous

Words that Start with On

  • On
  • Once
  • Oncoming
  • One
  • Oneida
  • Oneness
  • Onerous
  • Ones
  • Oneself
  • One-sided
  • Onesimus
  • Ongoing
  • Onion
  • Onions
  • Online
  • Onlooker
  • Onlookers
  • Only
  • Onset
  • Onslaught
  • Onto
  • Onward
  • Onwards
  • Ooze

Words that Start with Op

  • Opal
  • Opalescent
  • Opals
  • Opaque
  • Open
  • Opened
  • Opening
  • Openly
  • Open-minded
  • Openness
  • Opens
  • Opera
  • Operable
  • Operandi
  • Operas
  • Operate
  • Operated
  • Operates
  • Operatic
  • Operating
  • Operation
  • Operative
  • Operatives
  • Operator
  • Operators
  • Opiate
  • Opiates
  • Opine
  • Opined
  • Opinion
  • Opinionated
  • Opinions
  • Opium
  • Opossum
  • Opponent
  • Opponents
  • Opportune
  • Opportunely
  • Opportunities
  • Opportunity
  • Oppose
  • Opposed
  • Opposer
  • Opposers
  • Opposes
  • Opposing
  • Opposite
  • Opposites
  • Opposition
  • Oppositions
  • Oppress
  • Oppressed
  • Oppresses
  • Oppressing
  • Oppression
  • Oppressions
  • Oppressive
  • Oppressively
  • Oppressor
  • Oppressors
  • Opprobrious
  • Opprobrium
  • Opt
  • Optic
  • Optical
  • Optics
  • Optimal
  • Optimism
  • Optimist
  • Optimistic
  • Optimize
  • Optimum
  • Option
  • Optional
  • Options
  • Opulence
  • Opulent

Words that Start with Or

  • Or
  • Oracle
  • Oracles
  • Oracular
  • Oral
  • Orally
  • Oran
  • Orange
  • Oranges
  • Oration
  • Orations
  • Orator
  • Oratorical
  • Oratorio
  • Orators
  • Oratory
  • Orb
  • Orbit
  • Orbits
  • Orbs
  • Orchard
  • Orchards
  • Orchestra
  • Orchestral
  • Orchestras
  • Orchestrate
  • Orchid
  • Orchids
  • Ordain
  • Ordained
  • Ordaining
  • Ordains
  • Ordeal
  • Ordeals
  • Order
  • Ordered
  • Ordering
  • Orderlies
  • Orderliness
  • Orderly
  • Orders
  • Ordinaire
  • Ordinaires
  • Ordinance
  • Ordinances
  • Ordinarily
  • Ordinary
  • Ordination
  • Ordnance
  • Ordonnance
  • Ore
  • Ores
  • Organ
  • Organic
  • Organism
  • Organisms
  • Organist
  • Organization
  • Organizations
  • Organize
  • Organized
  • Organizer
  • Organizers
  • Organizing
  • Organs
  • Organum
  • Orgasm
  • Orgies
  • Orgy
  • Oriel
  • Orient
  • Oriental
  • Orientalist
  • Orientals
  • Orientate
  • Orientation
  • Oriented
  • Orifice
  • Orifices
  • Origen
  • Origin
  • Original
  • Originality
  • Originally
  • Originals
  • Originate
  • Originated
  • Originates
  • Originating
  • Origination
  • Originator
  • Originators
  • Origins
  • Oriole
  • Orisons
  • Ornament
  • Ornamental
  • Ornamentation
  • Ornamenting
  • Ornaments
  • Ornate
  • Ornery
  • Orphan
  • Orphaned
  • Orphans
  • Orthodox
  • Orthodoxy
  • Orthography

Words that Start with Os

  • Oscar
  • Oscillating
  • Oscillation
  • Oscillations
  • Osier
  • Osiers
  • Osman
  • Ostensible
  • Ostensibly
  • Ostentation
  • Ostentatious
  • Ostentatiously
  • Ostler
  • Ostracism
  • Ostrich
  • Ostriches

Words that Start with Ot, Ou

  • Other
  • Otherwise
  • Otter
  • Otters
  • Oud
  • Ought
  • Oughtn’t
  • Ounce
  • Ounces
  • Our
  • Ours
  • Ourselves
  • Oursler
  • Oust
  • Ousted
  • Out
  • Outa
  • Outbound
  • Outbreak
  • Outbreaks
  • Outbuildings
  • Outburst
  • Outbursts
  • Outcast
  • Outcasts
  • Outclass
  • Outcome
  • Outcries
  • Outcry
  • Outdated
  • Outdid
  • Outdo
  • Outdone
  • Outdoor
  • Outdoors
  • Outer
  • Outermost
  • Outfield
  • Outfit
  • Outfits
  • Outflanked
  • Outflow
  • Outgoing
  • Outgrow
  • Outgrown
  • Outgrowth
  • Outhouse
  • Outhouses
  • Outing
  • Outlandish
  • Outlast
  • Outlaw
  • Outlawed
  • Outlawry
  • Outlaws
  • Outlay
  • Outlet
  • Outlets
  • Outline
  • Outlined
  • Outlines
  • Outlining
  • Outlive
  • Outlived
  • Outlook
  • Outlying
  • Outmoded
  • Outnumber
  • Outnumbered
  • Outperform
  • Outpost
  • Outposts
  • Outpouring
  • Outpourings
  • Output
  • Outrage
  • Outraged
  • Outrageous
  • Outrageously
  • Outrages
  • Outraging
  • Outram
  • Outran
  • Outrank
  • Outreach
  • Outriders
  • Outright
  • Outro
  • Outros
  • Outrun
  • Outs
  • Outset
  • Outshine
  • Outshone
  • Outside
  • Outsider
  • Outsiders
  • Outsides
  • Outskirts
  • Outsmart
  • Outsource
  • Outspoken
  • Outspread
  • Outstanding
  • Outstretched
  • Outstrip
  • Outstripped
  • Outward
  • Outwardly
  • Outwards
  • Outweigh
  • Outweighed
  • Outweighs
  • Outwit
  • Outwitted
  • Outwork
  • Outworks
  • Outworn
  • Ouverte

Words that Start with Ov

  • Ova
  • Oval
  • Ovals
  • Ovaries
  • Ovary
  • Ovate
  • Ovation
  • Oven
  • Ovens
  • Over
  • Overactive
  • Overage
  • Overall
  • Overalls
  • Overawe
  • Overawed
  • Overbalance
  • Overbalanced
  • Overbearing
  • Overboard
  • Overborne
  • Overburden
  • Overburdened
  • Overcame
  • Overcast
  • Overcautious
  • Overcharged
  • Overcoat
  • Overcoats
  • Overcome
  • Overcomes
  • Overcoming
  • Overcook
  • Overcrowded
  • Overdo
  • Overdoing
  • Overdone
  • Overdraw
  • Overdrawn
  • Overdue
  • Overestimate
  • Overestimated
  • Overflow
  • Overflowed
  • Overflowing
  • Overflows
  • Overgrown
  • Overhang
  • Overhanging
  • Overhangs
  • Overhaul
  • Overhauled
  • Overhauling
  • Overhead
  • Overhear
  • Overheard
  • Overhearing
  • Overheated
  • Overhung
  • Overjoyed
  • Overladen
  • Overlaid
  • Overland
  • Overlap
  • Overlapping
  • Overlay
  • Overload
  • Overloaded
  • Overlook
  • Overlooked
  • Overlooking
  • Overlooks
  • Overlord
  • Overlying
  • Overmastered
  • Overmastering
  • Overmuch
  • Overnight
  • Overplus
  • Overpower
  • Overpowered
  • Overpowering
  • Overpowers
  • Overran
  • Overrate
  • Overrated
  • Overreach
  • Overreached
  • Override
  • Overrule
  • Overruled
  • Overruling
  • Overrun
  • Overrunning
  • Oversea
  • Overseas
  • Oversee
  • Overseer
  • Overseers
  • Overset
  • Overshadow
  • Overshadowed
  • Overshadowing
  • Overshadows
  • Overshoes
  • Overshot
  • Oversight
  • Overslept
  • Overspread
  • Overstep
  • Overstepped
  • Overstrained
  • Overt
  • Overtake
  • Overtaken
  • Overtakes
  • Overtaking
  • Overtaxed
  • Overthrew
  • Overthrow
  • Overthrowing
  • Overthrown
  • Overthrows
  • Overtime
  • Overton
  • Overtook
  • Overtop
  • Overtopped
  • Overture
  • Overtures
  • Overturn
  • Overturned
  • Overturning
  • Overview
  • Overweening
  • Overweight
  • Overwhelm
  • Overwhelmed
  • Overwhelming
  • Overwhelmingly
  • Overwhelms
  • Overwork
  • Overworked
  • Overwrought
  • Overzealous
  • Ovum

Words that Start with Ow, Ox, Oy

  • Owe
  • Owed
  • Owes
  • Owing
  • Owl
  • Owls
  • Owl’s
  • Own
  • Owned
  • Owner
  • Owners
  • Ownership
  • Owning
  • Owns
  • Ox
  • Oxalic
  • Oxen
  • Oxford
  • Oxidation
  • Oxide
  • Oxides
  • Oxidized
  • Oxidizing
  • Oxygen
  • Oyster
  • Oysters
  • Oz
  • Ozone
Words Starting with O
Words Starting with O – Created by 7ESL

Resources Related to Words with O

Discover more A-Z words articles:

Latest posts by Isabella Claire (see all)
Choose the dictionary – Word Finder lets you search for words based on the specific dictionary you select.
Loading...