im·​prob·​a·​ble | \(ˌ)im-ˈprä-bə-bəl, -ˈpräb-bəl\

Definition of improbable 

: unlikely to be true or to occur also : unlikely but real or true

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Other Words from improbable

improbability \(ˌ)im-​ˌprä-​bə-​ˈbi-​lə-​tē \ noun
improbably \(ˌ)im-​ˈprä-​bə-​blē, -​ˈpräb-​blē \ adverb

Synonyms & Antonyms for improbable


doubtful, dubious, far-fetched, flimsy, questionable, unapt, unlikely


likely, probable

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Examples of improbable in a Sentence

The team made an improbable comeback. it seems improbable that the two writers never met since they traveled in the same social circles

Recent Examples on the Web

When told an improbable story — for example, one in which a severely injured dog heals without medical care — most children tried to find a natural explanation. Galadriel Watson, Discover Magazine, "Why We Feel the Need to Knock On Wood," 17 Oct. 2018 Who in their time and in their way stood for freedom and stood for liberty and have made the American story the most improbable and most hopeful and most enduring story on earth. Megan Friedman, Town & Country, "Joe Biden Gave an Incredibly Powerful Speech at John McCain’s Memorial," 30 Aug. 2018 But in truth, in all but the steadiest hands, too much heady stuff tends to gum up the works in films that are mainly meant to showcase cool stunts and improbable plot twists, which this film has in spades. Alissa Wilkinson, Vox, "Mission: Impossible — Fallout is the most entertaining blockbuster of the summer," 17 July 2018 The rebirth of Hartford’s Colt factory complex — from 19th-century gunmaker to 21st-century mix of apartments, offices, classrooms and storefronts — is now in the final stretch of what at times appeared to be an improbable transformation. Kenneth R. Gosselin,, "Renovations Begin In Last Major Structure At Hartford's Colt Complex," 11 July 2018 Starlin Castro and Brian Anderson crushed home runs off Brewers reliever Josh Hader on consecutive pitches in the seventh inning, leading an improbable charge. Matthew Defranks,, "**Brewers Marlins head**," 10 July 2018 Another senator already facing the onslaught is Doug Jones of Alabama, a rare Southern Democrat who won an improbable special election late last year against scandal-laden Republican Roy Moore. NBC News, "Key senators already facing a campaign-like blitz on Kavanaugh confirmation fight," 10 July 2018 There are echoes of Germany's route to an improbable final in 2002., "Panic Stations: We Need to Talk About England's Knockout Record Before It Comes Home on July 15," 2 July 2018 Tomas Nosek scored the tiebreaking goal midway through the third period, and the expansion Golden Knights opened an improbable final with a thrilling 6-4 victory over the Washington Capitals on Monday night. New York Times, "Golden Knights Take Game 1 of Stanley Cup Finals," 29 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'improbable.' 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 improbable

1598, in the meaning defined above

History and Etymology for improbable

Middle French or Latin; Middle French, from Latin improbabilis, from in- + probabilis probable

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Last Updated

19 Nov 2018

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Time Traveler for improbable

The first known use of improbable was in 1598

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More Definitions for improbable



English Language Learners Definition of improbable

: not probable : not likely to be true or to happen


im·​prob·​a·​ble | \im-ˈprä-bə-bəl \

Kids Definition of improbable

: not likely : not probable improbable stories

Other Words from improbable

improbably \-​blē \ adverb an improbably happy ending

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Comments on improbable

What made you want to look up improbable? Please tell us where you read or heard it (including the quote, if possible).


the figure or shape of a crescent moon

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