Words that start with O
There are 500 words that start with o in this list, most common first. Filter by letters or length.
No words match that filter.
The most-used words that start with o, and what they mean
These are the 14 that come up most often in written English, so they are the ones worth knowing first.
- other
- adjectiveSee other (determiner) below.
- over
- adjectiveFinished; ended; concluded.
- order
- noun(countable) A command.
- others
- nounOther people.
- open
- adjective(usually not comparable) Physically unobstructed, uncovered, etc.
- organization
- noun(countable) A group of people or other legal entities with an explicit purpose and written rules.
- object
- nounA thing that has physical existence but is not alive.
- original
- adjective(not comparable) Newly created.
- obtained
- verb(transitive) To get hold of; to gain possession of, to procure; to acquire, in any way.
- observed
- adjective(of a holiday) Exceptionally celebrated on a date other than the usual date.
- operation
- noun(uncountable) The act or process of operating (verb): agency; the exertion of power, physical, mechanical, or moral.
- opinion
- nounA belief, judgment or perspective that a person has formed, either through objective or subjective reasoning, about a topic, issue, person or thing.
- operations
- nounThe department or interdepartmental team within a company that works on optimizing the company's execution of such things.
- objects
- nounA thing that has physical existence but is not alive.
Nouns, verbs and adjectives
Of the 500 words in this list, 321 can be used as a noun, including other, over, order, others, open. Plenty of words do more than one job: state is a noun, a verb and an adjective depending on how you use it, which is why these numbers add up to more than the list itself.
How this list is built
The words come from the Datamuse language API, then get cleaned up, because the raw output is not much use on its own. Each word is checked against an English dictionary, with a frequency floor for anything not in it, so ordinary inflections survive while noise does not. Roman numerals, fragments and vowel-less abbreviations are stripped out.
What is left is ranked by how often each word actually appears in written English. That ordering is the point: it puts the words you might actually want at the top. The full method is on how we build these.
Common questions
How many words that start with o are there?
This list holds 500, filtered to real dictionary words and ranked by how common they are. English has more if you count obscure and archaic ones, but they are little use to anybody.
Can a word starting with O be a noun?
Yes. 321 of the 500 words on this list can be used as a noun. The breakdown above shows how many work as verbs, adjectives and adverbs too.
How are the words ordered?
By how often each word appears in written English, most common first, so the useful ones are at the top rather than buried under rarities. See how we build these.
Can I search inside the list?
Yes. The filter box narrows the list as you type, and where a list mixes lengths there are buttons to show only words of a given length.