Words Starting With O

All 397 English words beginning with O, from 2 to 14 letters, grouped by length with the longest and most useful highlighted.

Words in this list: 397
Word lengths: 2–14 letters
Most common length: 8 letters (69)
Shortest: od, oe, of
Longest: organizational

8-letter words are the largest group here — 69 words, 17% of the list.

The longest entry is “organizational” (14 letters); the shortest are “od”, “oe”, “of”.

The most frequently used are “of”, “on”, “or”, “our”, “one”.

This list is built from this site’s own word list of about 16,750 words drawn from common written English. It includes some names and abbreviations that most word games reject, and it leaves out rare and technical words, so check anything you plan to play against the rules of your game. More about the word list.

397 wordsshowing 302

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2-letter words (10 of 13)

3-letter words (17 of 22)

4-letter words (29 of 38)

oaks
oath
obey
odds
odor
offs
ohio
oils
okay
olds
oman
omar
omit
omni
once
ones
only
onto
onyx
oops
opal
open
opus
oral
orgy
orig
oslo
otis
otto

5-letter words (27 of 36)

oasis
obese
occur
ocean
octet
offer
often
older
olive
olson
omaha
omega
onion
onset
opens
opera
opted
optic
orbit
order
organ
orion
ortho
osaka
oscar
other
otter

6-letter words (37 of 49)

object
obtain
occult
occupy
occurs
oceans
octave
odessa
offers
office
offset
oldest
oldies
oliver
olivia
onions
online
opaque
opened
opener
openly
oppose
optics
option
oracle
orange
orchid
orders
oregon
organs
orgasm
orgies
orient
origin
orphan
others
ottawa

7-letter words (48 of 64)

oakland
oakwood
obesity
objects
obliged
oblique
obscene
obscure
observe
obvious
oceania
oceanic
october
odyssey
offence
offense
offered
officer
offices
offline
olivier
olympia
olympic
olympus
omitted
onboard
oneself
ongoing
ontario
onwards
opening
operate
opinion
opposed
optical
optimal
optimum
options
orbital
orchard
ordered
organic
orgasms
origins
orioles
orlando
orleans
ottoman

8-letter words (52 of 69)

obituary
observed
observer
obsessed
obsolete
obstacle
obtained
occasion
occupied
occurred
offences
offended
offender
offenses
offering
officers
official
offshore
oklahoma
olympics
omission
oncology
ontology
openings
openness
operated
operates
operator
opinions
opponent
opposing
opposite
optimism
optimize
optional
ordering
ordinary
organise
organism
organize
oriental
oriented
original
ornament
orthodox
outbound
outbreak
outcomes
outdated
outdoors
outgoing
outlined

9-letter words (34 of 45)

obedience
objection
objective
obligated
observers
observing
obsession
obstacles
obtaining
obviously
occasions
occupancy
occurring
offenders
offensive
offerings
officials
offspring
ombudsman
omissions
operating
operation
operative
operators
opponents
optimized
orchestra
ordinance
ordinator
organised
organisms
organized
organizer
originals

10-letter words (24 of 32)

obituaries
objections
objectives
obligation
obstetrics
occasional
occupation
occurrence
officially
oldsmobile
operations
opposition
oppression
optimistic
optimizing
optionally
ordinances
ordination
organising
organizers
organizing
originally
originated
originator

11-letter words (11 of 14)

obligations
observation
observatory
obstruction
occupations
occurrences
operational
opportunity
orientation
originating
outstanding

12-letter words (6 of 8)

observations
occasionally
occupational
optimization
organisation
organization

13-letter words (5)

objectionable
ophthalmology
opportunities
optimizations
organizations

14-letter words (2)

organisational
organizational

Showing 302 of 397 words — 95 more available.

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