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.
Many are leaning into their own unsubstantiated suppositions, even those not backed by evidence. — Rebekah Riess, CNN Money, 22 Aug. 2026 Recent actions by the FCC have called that supposition into question. — Jim Fisher, PC Magazine, 10 Aug. 2026 Now Kennedy took her suppositions even further, reexamining the literature on a famous Olmec site where thousands of toad skeletons had been excavated. — Kimon De Greef, Longreads, 4 Aug. 2026 Of course, this is all a supposition and one that will only happen at some point in the future. — Lizzie Lanuza, StyleCaster, 3 Aug. 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 1 Sep. 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

Britannica.com: Encyclopedia article about supposition

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