one

1 of 2

noun

Synonyms of onenext
1
: the first whole number above zero see Table of Numbers
2
: the number denoting unity
3
a
: the first in a set or series
often used with an attributive noun
day one
b
: an article of clothing of a size designated one
wears a one
4
: a single person or thing
has the one but needs the other
5
: a one-dollar bill
see also:

-one

2 of 2

noun suffix

: ketone or related or analogous compound or class of compounds
lactone
quinone

Examples of one in a Sentence

Noun one, two, three, four, … I don't have any ones. Can you break a five? I'll be there at one.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
Yes, no one deserves to be cheated on, and Kyle could have been better about obeying the rules, but four years? Brian Moylan, Vulture, 3 June 2026 If the second section presents the diagnosis, then in the footnote to Howl Ginsberg writes a prescription, because if we’re oppressed by a dark faith then the only antidote is a different one. Literary Hub, 3 June 2026 And in a city as deep-blue as this one, the Democratic primary is the most consequential contest of the election year. Jenny Gathright, Washington Post, 3 June 2026 The best Teflon pans are not just the newest or most expensive ones. Ryan Brennan june 2, Sacbee.com, 3 June 2026 See All Example Sentences for one

Word History

Etymology

Noun suffix

International Scientific Vocabulary, alteration of -ene

First Known Use

Noun

before the 12th century, in the meaning defined at sense 1

Time Traveler
The first known use of one was before the 12th century

Browse Nearby Words

Cite this Entry

“One.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/one. Accessed 9 Jun. 2026.

Kids Definition

one

1 of 3 adjective
ˈwən How to pronounce one (audio)
ˌwən
1
: being a single unit or thing see number
2
: being a certain unit or thing
early one morning
3
a
: being the same in kind or quality
members of one class
b
: not divided
4
: not definitely fixed or placed
will see you again one day
5
: only entry 1 sense 2a
the one person they wanted to see

one

2 of 3 noun
1
: the number indicating a single unit
2
: the first in a set or series
3
: a single person or thing
has the one, but needs the other
4
: a one-dollar bill

one

3 of 3 pronoun
1
: a single member or individual
saw one of your friends
2
: any person
one never knows

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