supposition

noun

sup·​po·​si·​tion ˌsə-pə-ˈzi-shən How to pronounce supposition (audio)
Synonyms of supposition
1
: something that is supposed : hypothesis
2
: the act of supposing
suppositional
ˌsə-pə-ˈzi-sh(ə-)nəl How to pronounce supposition (audio)
adjective

Synonyms of supposition

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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The past eight months have exposed both suppositions. — Liam Twomey, New York Times, 11 Mar. 2026 And while it has been mentioned in this space that draft capital for Norman Powell might be one way to go for the Heat, that was based on the supposition of Tyler stepping in as a scoring leader. — Ira Winderman, Sun Sentinel, 20 Jan. 2026 What becomes alarmingly evident through the key assumptions check is how many of the current responses expect a quick resolution of the conflict — a supposition that is unsound, or at least unsupported. — Judd Devermont, semafor.com, 27 Apr. 2026 The nature of Tech’s loss only supports the supposition that, without Texas and Oklahoma, the Big 12 is sorely lacking in top-tier talent. — Kevin Sherrington jan. 1, Dallas Morning News, 1 Jan. 2026 See All Example Sentences for supposition

Word History

Etymology

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

Phrases Containing supposition

Rhymes for supposition

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Browse Nearby Words

supposit
supposition
suppositional
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Cite this Entry

“Supposition.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/supposition. Accessed 7 Jul. 2026.

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Kids Definition

supposition

noun
sup·​po·​si·​tion ˌsəp-ə-ˈzish-ən How to pronounce supposition (audio)
1
: something that is supposed
2
: the act of supposing
suppositional
-ˈzish-nəl How to pronounce supposition (audio)
-ən-ᵊl
adjective

More from Merriam-Webster on supposition

Nglish: Translation of supposition for Spanish Speakers

Britannica.com: Encyclopedia article about supposition

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