Words That Start With O

800 words Words by letter Checked 9 Oct 2026

These words that start with O come from a standard English dictionary used for word games, ranked by how often each word is used in everyday writing. There are 800 words starting with O on this page. The 100 most common come first, each with a short meaning, followed by shorter, longer and easier picks and a filter for any ending or length.

O has 800 words, and its opening rows are full of small, busy ones like "on", "out" and "over". These appear in nearly every sentence, so they are worth learning early.

Longer O words often start with "op" or "or", as in "opportunity", "organization" and "original". Spellers often forget the doubled P in "opportunity", so it earns a spot on any practice list. O even holds its own opposites: "on" and "off" both live on this page, which is handy for a quick game with younger children.

Words starting with O: 800
Most used: of
Longest common one: organizational 14 letters
Nouns, verbs, adjectives: 378, 112, 152

Most common words that start with O

Ranked by how often the word appears in English text. "Type" is the word's main part of speech.

#	Word	Meaning	Type
1	of	no short meaning listed
2	on	with a forward motion	adv.
3	or	a state in northwestern United States on the Pacific	noun
4	one	used of a single unit or thing; not two or more	adj.
5	out	not allowed to continue to bat or run	adj.
6	other	not the same one or ones already mentioned or implied; - the White Queen	adj.
7	our	no short meaning listed
8	only	and nothing more	adv.
9	over	at or to a point across intervening space etc.	adv.
10	off	from a particular thing or place or position (`forth' is obsolete)	adv.
11	old	(used especially of persons) having lived for a relatively long time or attained a specific age	adj.
12	own	belonging to or on behalf of a specified person (especially yourself); preceded by a possessive	adj.
13	once	on one occasion	adv.
14	order	(often plural) a command given by a superior (e.g., a military or law enforcement officer) that must be obeyed	noun
15	open	cause to open or to become open	verb
16	oh	a midwestern state in north central United States in the Great Lakes region	noun
17	others	no short meaning listed
18	often	many times at short intervals	adv.
19	office	place of business where professional or clerical duties are performed	noun
20	outside	relating to or being on or near the outer side or limit	adj.
21	original	preceding all others in time or being as first made or performed	adj.
22	official	a worker who holds or is invested with an office	noun
23	oil	a slippery or viscous liquid or liquefiable substance not miscible with water	noun
24	okay	being satisfactory or in satisfactory condition	adj.
25	offer	make available or accessible, provide or furnish	verb
26	officer	any person in the armed services who holds a position of authority or command	noun
27	opportunity	a possibility due to a favorable combination of circumstances	noun
28	opening	an open or empty space in or between things	noun
29	opinion	a personal belief or judgment that is not founded on proof or certainty	noun
30	older	advanced in years; (`aged' is pronounced as two syllables)	adj.
31	operation	the state of being in effect or being operative	noun
32	organization	a group of people who work together	noun
33	overall	involving only main features	adj.
34	otherwise	in other respects or ways	adv.
35	operations	financial transactions at a brokerage; having to do with the execution of trades and keeping customer records	noun
36	owner	(law) someone who owns (is legal possessor of) a business	noun
37	obviously	unmistakably (`plain' is often used informally for `plainly')	adv.
38	option	the right to buy or sell property at an agreed price	noun
39	onto	no short meaning listed
40	ocean	a large body of water constituting a principal part of the hydrosphere	noun
41	originally	in an original manner	adv.
42	obvious	easily perceived by the senses or grasped by the mind	adj.
43	opposite	being directly across from each other; facing; - Longfellow	adj.
44	orange	round yellow to orange fruit of any of several citrus trees	noun
45	ourselves	no short meaning listed
46	offering	something offered (as a proposal or bid)	noun
47	opposition	the action of opposing something that you disapprove or disagree with	noun
48	object	a tangible and visible entity; an entity that can cast a shadow	noun
49	origin	the place where something begins, where it springs into being	noun
50	officially	in an official role	adv.
51	operate	direct or control; projects, businesses, etc.	verb
52	outstanding	distinguished from others in excellence	adj.
53	occur	come to pass	verb
54	offensive	violating or tending to violate or offend against	adj.
55	output	final product; the things produced	noun
56	odd	not divisible by two	adj.
57	op	no short meaning listed
58	ordinary	not exceptional in any way especially in quality or ability or size or degree	adj.
59	obtain	come into possession of	verb
60	organic	relating or belonging to the class of chemical compounds having a carbon basis	adj.
61	ownership	the relation of an owner to the thing possessed; possession with the right to transfer possession to others	noun
62	occasionally	now and then or here and there	adv.
63	occasion	an event that occurs at a critical time	noun
64	oxford	a city in southern England to the northwest of London; site of Oxford University	noun
65	objective	the goal intended to be attained (and which is believed to be attainable)	noun
66	organisation	the persons (or committees or departments etc.) who make up a body for the purpose of administering something	noun
67	ought	no short meaning listed
68	outcome	something that results	noun
69	ongoing	currently happening	adj.
70	operator	(mathematics) a symbol or function representing a mathematical operation	noun
71	overseas	beyond or across the sea	adv.
72	odds	the likelihood of a thing occurring rather than not occurring	noun
73	opera	a drama set to music	noun
74	overcome	win a victory over	verb
75	occasions	something you have to do	noun
76	offense	a lack of politeness; a failure to show regard for others; wounding the feelings or others	noun
77	oral	using speech rather than writing	adj.
78	outer	being on the outside or further from a center	adj.
79	oxygen	a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas	noun
80	outdoor	located, suited for, or taking place in the open air	adj.
81	outfit	any cohesive unit such as a military company	noun
82	operational	pertaining to a process or series of actions for achieving a result	adj.
83	occupation	the principal activity in your life that you do to earn money	noun
84	opponent	a contestant that you are matched against	noun
85	overnight	during or for the length of one night	adv.
86	oak	the hard durable wood of any oak; used especially for furniture and flooring	noun
87	ours	no short meaning listed
88	organ	a fully differentiated structural and functional unit in an animal that is specialized for some particular...	noun
89	observation	the act of making and recording a measurement	noun
90	owe	be obliged to pay or repay	verb
91	occasional	occurring from time to time	adj.
92	openly	in an open way	adv.
93	overview	a general summary of a subject	noun
94	ore	a mineral that contains metal that is valuable enough to be mined	noun
95	os	a mouth or mouthlike opening	noun
96	olive	of a yellow-green color similar to that of an unripe olive	adj.
97	obligation	the social force that binds you to the courses of action demanded by that force; ; - John D.Rockefeller Jr	noun
98	optical	of or relating to or involving light or optics	adj.
99	outlook	a habitual or characteristic mental attitude that determines how you will interpret and respond to situations	noun
100	observe	discover or determine the existence, presence, or fact of	verb

Easy words that start with O for kids

Everyday words most children meet early, good for spelling lists and word games.

one
out
other
our
only
over
off
old
own
once
order
open
others
often
office
oil
okay
offer
older
owner
option
onto
ocean
orange
object
origin
occur
output
odd
obtain
oxford
ought

Short words that start with O

Two to four letters.

of
on
or
one
out
our
only
over
off
old
own
once
open
oh
oil
okay
onto
odd
op
odds
oral
oak
ours
owe
ore
os
oven
oval
oath
opt
owl
obey
ops
ooh
ole
oops
otto
ow
ons
ouch

5 letter words starting with O

other
order
often
offer
older
owner
ocean
occur
ought
opera
outer
organ
olive
orbit
onion
ounce
omega
onset
obese
oxide
optic
oasis
oddly
ozone

All 5 letter words that start with O, with a Wordle helper

Long words that start with O

Ten letters or more.

opportunity
organization
operations
originally
opposition
officially
outstanding
occasionally
organisation
operational
occupation
observation
occasional
obligation
orientation
optimistic
organizational
oppression
occurrence
outrageous
overweight
occupational
observatory
optimization
overlapping
obstruction
overwhelmingly
oppressive
ordination
obligatory

Words that start and end with O

onto
otto
overdo
ortho
oregano
outdo
oxo
oratorio
ordo
octavo
oho
olio

Filter all 800 words that start with O

Narrow the full list by ending, letters inside and length. The list updates as you type.

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Questions people ask

How many words start with O?

This list has 800 words starting with O, taken from a standard word-game dictionary and limited to words that appear in real English text.

What are the most common words that start with O?

of, on, or, one, out, other, our, only are the most used in everyday English.

What are some long words that start with O?

opportunity, operation, organization, otherwise, operations.

What are easy words that start with O for kids?

of, on, or, one, out, other are short, everyday examples.

Source: the ENABLE word list (a public-domain dictionary used for word games), ranked by how often each word appears in English text (the open wordfreq project), with short meanings from Princeton WordNet. Offensive words are left out.

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