sup·​po·​si·​tion | \ ˌsə-pə-ˈzi-shən How to pronounce supposition (audio) \

Definition of supposition

1 : something that is supposed : hypothesis
2 : the act of supposing

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Other Words from supposition

suppositional \ ˌsə-​pə-​ˈzish-​nəl How to pronounce suppositional (audio) , -​ˈzi-​shə-​nᵊl \ adjective

Synonyms for supposition


hypothesis, proposition, theory, thesis

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Examples of supposition in a Sentence

a supposition that proved correct This is just idle supposition.

Recent Examples on the Web

At least then Google’s at the mercy of facts, not Twitter supposition. Hayden Dingman, PCWorld, "Google shows off Stadia streaming games: Cyberpunk 2077, Mortal Kombat 11, and more," 19 Aug. 2019 This isn’t just supposition; Texas provides a disturbing preview. Melissa Gira Grant, The New Republic, "Trump’s Title X Restrictions Are Nothing Short of Coercion," 20 Aug. 2019 Prince’s grumbling supposition of anger and blame expressed the last days of the Obama era, when facts of black demoralization were left unaddressed. Armond White, National Review, "The Baltimore Culture Wars: A History," 31 July 2019 And that need for control is what takes me back to our supposition of a fake news critique lying at the heart of Far From Home. Alissa Wilkinson, Vox, "Spider-Man: Far From Home turns a class-conscious hero into a tech bro," 3 July 2019 The tale-of-the-tape genre itself is steeped in myth, supposition, educated guesses and excited ambition. Gary Peterson, The Mercury News, "When it comes to bombs like Evan Longoria’s, trust your eyes, not so much the tape measure," 3 July 2019 The supposition was solidified as the Rockies lined baseballs off Walker Buehler through the sweltering, thin air, making Buehler look nothing like the man who had arguably been the best pitcher in baseball in June. Jorge Castillo,, "Dodgers pull away in the ninth to win slugfest against the Rockies," 28 June 2019 Sometimes Mr Eimer relies too heavily on anecdote and supposition. The Economist, "A writer’s journey through Myanmar," 21 June 2019 The not-so-unreasonable supposition that Sanders could have beaten Donald Trump, along with a new solid base of activist support, made him an instant frontrunner for the Democratic nomination in 2020. Matthew Zeitlin, The New Republic, "Bernie’s Red Vermont," 13 June 2019

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

15th century, in the meaning defined at sense 1

History and Etymology for supposition

Middle English supposicioun, from Anglo-French supposicion, from Late Latin supposition-, suppositio, from Latin, act of placing beneath, from supponere

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Statistics for supposition

Last Updated

9 Sep 2019

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Time Traveler for supposition

The first known use of supposition was in the 15th century

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English Language Learners Definition of supposition

: an idea or theory that you believe is true even though you do not have proof

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Comments on supposition

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


to make a temporary encampment

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