\ ˈwən(t)s How to pronounce once (audio) \

Definition of once

 (Entry 1 of 4)

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 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



Definition of once (Entry 2 of 4)

: one single time : one time at least Please be on time this once.
at once
1 : at the same time : simultaneously
3 : both entry 2 at once funny and sad

Definition of once (Entry 3 of 4)

: that once was : former a once successful actor

Definition of once (Entry 4 of 4)

: at the moment when : as soon as Once she spoke, I recognized her.

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Synonyms for once

Synonyms: Adverb

Synonyms: Adjective

Synonyms: Conjunction

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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
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Recent Examples on the Web: Adverb For the first time, NASA will test-fire all four engines at once on its new Space Launch System, which will hopefully be ready to fly to the moon in 2022. Mary Perez And Lauren Walck | The Sun Herald, NOLA.com, "NASA to test engines for 'most powerful rocket ever' in Mississippi this weekend," 15 Jan. 2021 Infectious Diseases has launched the ACTIV-2 trial, which aims to test several medications at once. Globe Staff, BostonGlobe.com, "Researchers test common drugs in quest for treatments for early COVID-19," 14 Jan. 2021 James Wiseman is a work in progress and a revelation, all at once. Bruce Jenkins, SFChronicle.com, "On a murky night, Warriors’ big picture has clarity," 13 Jan. 2021 The network can't carry much data at once, but these smart home gadgets don't necessarily need much bandwidth to stay online. David Nield, Wired, "How Amazon Sidewalk Works—and Why You May Want to Turn It Off," 13 Jan. 2021 Players hit multiple balls at once, encountering bizarre rules and challenging obstacles. Gieson Cacho, Star Tribune, "These video games will tide you over during the long winter," 13 Jan. 2021 Nothing in human history has monitored 2.7 billion people at once. Siva Vaidhyanathan, The New Republic, "Making Sense of the Facebook Menace," 5 Jan. 2021 Vernon said data suggest that more gunmen are getting out of their cars and shooting multiple targets at once, at close range, and that more people are driving around with guns at the ready. Kevin Rector, Los Angeles Times, "A year like no other for L.A. crime: Homicides surge, robberies and rapes drop," 3 Jan. 2021 Compound exercises are movements that work multiple muscle groups at once, as opposed to isolation exercises, which recruit just one muscle group at a time (say, a single-arm row versus a single-arm bicep curl). Jenny Mccoy, SELF, "A Full-Body Workout You Can Do in Just 15 Minutes," 1 Jan. 2021 Recent Examples on the Web: Noun In many newsrooms, including at the once staunchly anti-union Los Angeles Times, journalists have organized in order to gain a degree of control over their lives. Robin Kaiser-schatzlein, The New Republic, "The Artist Isn’t Dead," 4 Jan. 2021 The upside of it is that you may be rewarded with a once in a lifetime buck that has probably never seen a human being. Hal Blood, Outdoor Life, "3 Great Places to Take a Stand in the Big Woods," 10 Nov. 2020 Several governors, including Andrew Cuomo of the once hotspot New York, have decided to ignore the CDC’s guidelines, sticking with previous testing advice. Sara Kiley Watson, Popular Science, "The CDC’s new COVID-19 testing guidelines could make the pandemic worse," 27 Aug. 2020 The wayward beluga was captured on video by Gone Whale Watching owner and boat captain Domenic Biagini who flew a drone to get the once in a lifetime shot. Alex Fox, Smithsonian Magazine, "In a Rare Sighting, Wayward Beluga Spotted Off San Diego," 16 July 2020 The second-year quarterback completed 10 of 13 passes for 113 yards, led two scoring drives in three series of action and once again showed play-making ability with his feet. Dave Birkett, Detroit Free Press, "Detroit Lions' stock watch: Rookie LB Jalen Reeves-Maybin a bright spot," 25 Aug. 2017 Recent Examples on the Web: Adjective Mandy Moore, his once-girlfriend, expressed her excitement for him, as did Valderrama’s longtime friend Avril Lavigne and former co-star Eiza González. Lydia Wang, refinery29.com, "Wilmer Valderamma & Fiancé Amanda Pacheco Are Expecting First Child," 21 Dec. 2020 Over the last few decades, its once majority of white workers were replaced with immigrants who together speak more than 80 languages. Los Angeles Times, "A tale of two cities: the cautious refugees hit by COVID-19 and those who call it a hoax and refuse masks," 18 Dec. 2020 Coming out in the midst of a Vatican corruption scandal dominating Italian headlines for months, the film provided a nostalgic profile of a once globe-trotting papacy that in some ways ended with COVID-19. Nicole Winfield, Anchorage Daily News, "Fiasco intensifies over pope’s quote endorsing same-sex civil unions," 23 Oct. 2020 Over the past two decades plus there's been an incredible amount of amazing horror programming that has totally changed the landscape of how viewers enjoy the once niche genre. Rosie Knight, refinery29.com, "When Did TV Get So Scary? 21 Horror Shows That Took Us From From Teen Drama To Abject Terror," 24 Sep. 2020 Weeds now wind through the paving stones at the once grand entrance. Ruth Eglash, Washington Post, "Once an oasis of peace, Jericho now fears Israeli annexation," 29 June 2020 Brazil meanwhile were beaten by hosts France in the last 16; a disappointing but not unexpected finish from a once world class squad. SI.com, "England vs Brazil Preview: Where to Watch, Live Stream, Kick Off Time & Team News," 4 Oct. 2019 And Michigan's gone through spring drills without a clear answer of who will realistically be the front-runner once summer begins. Nick Baumgardner, Detroit Free Press, "Michigan football's Shea Patterson still competing despite unclear situation," 12 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'once.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of once


12th century, in the meaning defined at sense 1


13th century, in the meaning defined at sense 1


1620, in the meaning defined above


1747, in the meaning defined above

History and Etymology for once

Adverb, Noun, Adjective, and Conjunction

Middle English ones, from genitive of on one

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Time Traveler for once

Time Traveler

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

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Statistics for once

Last Updated

21 Jan 2021

Cite this Entry

“Once.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/once. Accessed 22 Jan. 2021.

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More Definitions for once


How to pronounce once (audio)

English Language Learners Definition of once

 (Entry 1 of 3)

: one time only
: at any one time
: at some time in the past



English Language Learners Definition of once (Entry 2 of 3)

: one single time

English Language Learners Definition of once (Entry 3 of 3)

: at the moment when : as soon as


\ ˈwəns How to pronounce once (audio) \

Kids Definition of once

 (Entry 1 of 3)

1 : one time only It happened just once.
2 : at some time in the past : formerly It was once done that way.
3 : at any one time : ever She didn't once thank me.
once and for all
: now and for the last time That should solve the problem once and for all.
once in a while
: from time to time I play golf once in a while.



Kids Definition of once (Entry 2 of 3)

: one single time We can make an exception just this once.
at once
1 : at the same time I can't understand with both of you talking at once.
2 : immediately sense 2 Leave at once.

Kids Definition of once (Entry 3 of 3)

: as soon as : when Once you've finished your homework, you may go outside.

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Comments on once

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