once

1 of 4

adverb

1
: one time and no more
rode a horse only once
went skydiving once
2
: at any one time : under any circumstances : ever
didn't once thank me
3
: at some indefinite time in the past : formerly
was once a booming mining town
4
: by one degree of relationship
first cousin once removed

once

2 of 4

noun

: one single time : one time at least
Please be on time this once.

once

3 of 4

adjective

: that once was : former
… contributions to enrich the legal resources of the once province of Britain.J. N. Pomeroy

once

4 of 4

conjunction

: at the moment when : as soon as
Once she spoke, I recognized her.
Phrases
once and for all
1
: with finality : definitively
The team proved once and for all that they are the best.
2
: for the last time
I'm telling you once and for all that I'm not going.
once in a while
: now and then
spent most of their time at home, but went out once in a while
at once
1
: at the same time : simultaneously
2
3
: both entry 2
at once funny and sad

Examples of once in a Sentence

Adverb I will repeat the question once. The play was performed only once. She didn't once thank me. He didn't look at me once. It was once done that way. A river once flowed through this canyon. It was once a booming mining town. Their music was once very popular. Noun I have tried Indian food more than once. Please be on time just this once. For once you seem to know what I'm talking about. Adjective the once child star is now a lawyer in the entertainment industry Conjunction Once she spoke, I recognized her. you should have stopped wrestling once you knew someone was getting hurt, not five minutes later
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.
Adverb
Plans vary on how to best raise it once stabilized. Barbie Latza Nadeau, CNN, 1 Dec. 2024 There was a first-cousin match on the paternal line, and a first cousin once removed on the maternal line. Sarah Weinman, Rolling Stone, 1 Dec. 2024
Noun
While the front-of-house was abuzz with celebrities vying to be noticed, the once dapper and demure designers in the mold of a Christian Dior or Hubert de Givenchy were now being replaced by upstarts like John Galliano and Alexander McQueen. Ivan Shaw, Vogue, 18 June 2024 Here are some highlights of ready-to-wear collections Thursday: GIVENCHY GETS FEMININE The once-street and urban Matthew M. Williams uttered a word not often heard describing his designs: Elegant. Thomas Adamson, ajc, 2 Mar. 2023
Adjective
The downsizing trend reflects broader shifts in marketing as the once staple of American living rooms, thick catalogs from brands like Sears and J.C. Penney have dwindled and been replaced by compact mailings and digital platforms. Natalie Venegas, Newsweek, 30 Nov. 2024 As job gains dropped off from their once breakneck pace, economists were quick to note that the labor market was merely slowing and not at risk of imminent collapse. Alicia Wallace, CNN, 4 Oct. 2024 See all Example Sentences for once 

Word History

Etymology

Adverb, Noun, Adjective, and Conjunction

Middle English ones, from genitive of on one

First Known Use

Adverb

12th century, in the meaning defined at sense 1

Noun

13th century, in the meaning defined at sense 1

Adjective

1620, in the meaning defined above

Conjunction

1747, in the meaning defined above

Time Traveler
The first known use of once was in the 12th century

Dictionary Entries Near once

Cite this Entry

“Once.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/once. Accessed 15 Dec. 2024.

Kids Definition

once

1 of 3 adverb
1
: one time only
will repeat the question once
2
: at any one time : ever
once you hesitate, it's too late
3
: at some time in the past : formerly
it was once done that way
4
: by one degree of relationship
cousin once removed

once

2 of 3 noun
: one single time
just this once

once

3 of 3 conjunction
: as soon as
once that is done, all will be well

More from Merriam-Webster on once

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!