sup·​po·​si·​tion ˌsə-pə-ˈzi-shən How to pronounce supposition (audio)
: something that is supposed : hypothesis
: the act of supposing
ˌsə-pə-ˈzish-nəl How to pronounce supposition (audio)

Example Sentences

a supposition that proved correct This is just idle supposition.
Recent Examples on the Web For pretty much all his life, Harry has been trailed by photographers, rumors, headlines, supposition and reporters endlessly shouting questions at him. Los Angeles Times, 10 Jan. 2023 To add firmness to this section Timothy Parsons engages in supposition and extrapolation. Razib Khan, Discover Magazine, 25 June 2010 Boudreaux said there could have been another person involved, perhaps as a getaway driver, but that is supposition at this point. Los Angeles Times, 18 Jan. 2023 The supposition by many political observers is that the about-face has largely been motivated by an impending White House bid. Dean Obeidallah, CNN, 29 Jan. 2023 Gregor Mendel's supposition that there were discrete elements which mediated biological inheritance had the virtue of being correct. Razib Khan, Discover Magazine, 8 Oct. 2013 My own earlier supposition has been that northeast Europe served as a repository of peoples who adopted agriculture late, and were resistant to the expansion of Indo-Europeans. Razib Khan, Discover Magazine, 19 Feb. 2012 In some circumstances the utilization of statistics is a matter of style, to firm up a flimsy supposition with the rigorous garb of quantity. Razib Khan, Discover Magazine, 21 Nov. 2012 This supposition has long led pundits to argue that the nation’s growing demographic pluralism will inevitably produce a more progressive electorate. Daniel Martinez Hosang, The New Republic, 9 Dec. 2022 See More

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.

Word History


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

First Known Use

15th century, in the meaning defined at sense 1

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

Dictionary Entries Near supposition

Cite this Entry

“Supposition.” Dictionary, Merriam-Webster, Accessed 22 Mar. 2023.

Kids Definition


sup·​po·​si·​tion ˌsəp-ə-ˈzish-ən How to pronounce supposition (audio)
: something that is supposed
: the act of supposing
-ˈzish-nəl How to pronounce supposition (audio)

More from Merriam-Webster on supposition

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!

What Did You Just Call Me?

  • brown chihuahua sitting on the floor with squinting eyes looking at the camera
  • Before we went to her house, Hannah told us her aunt was a flibbertigibbet.
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

Solve today's spelling word game by finding as many words as you can with using just 7 letters. Longer words score more points.

Can you make 12 words with 7 letters?