one

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:

Examples of one in a Sentence

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.
The United States at that time had still not determined who was responsible, but Trump said the two pilots were fine and no one had been injured. Joey Garrison, USA Today, 10 June 2026 What no one is asking is how Whitney feels about any of this. Brian Moylan, Vulture, 10 June 2026 The Hurricanes came out roaring in the first period in this one as well, scoring three goals to the Golden Knights’ one by captain Mark Stone. Scott Thompson, FOXNews.com, 10 June 2026 That one was just a little down. Gabrielle Starr, Boston Herald, 10 June 2026 See All Example Sentences for one

Word History

Etymology
First Known Use

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 11 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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