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

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 Its listing is largely rhetoric-free, and makes no suppositions about the perpetrators in the absence of evidence. Holman W. Jenkins, WSJ, "How the News Became Fake," 25 Jan. 2019 Benjamin Brafman, Weinstein's attorney, quickly rebuffed that supposition, noting that the original charges could have meant 25 years behind bars and that the producer can stay in the Connecticut home through next year. Richard Winton,, "Harvey Weinstein pleads not guilty to new charges; judge lets him stay free," 9 July 2018 These Marist’s findings (showing that undecided voters are more likely to be women and more likely to be moderate or conservative) would seem to confirm that supposition. Dylan Scott, Vox, "Six important facts about the voters still undecided in the 2018 midterms.," 22 Oct. 2018 No one knows, but after years of supposition and pie-in-the-sky conjecture from planners and passengers alike, BART officials are starting to study a second Transbay Tube. Michael Cabanatuan, San Francisco Chronicle, "BART gets serious about a 2nd East Bay-S.F. Transbay Tube," 21 Feb. 2018

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

15 Jul 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

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food or victuals

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