supposition

noun

ˌsə-pə-ˈzi-shən How to pronounce supposition (audio)
Definition of suppositionnext
1
as in hypothesis
an idea that is the starting point for making a case or conducting an investigation my supposition is that this grape variety, which flourishes in southern France, should do equally well here, given the similar climate

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2
as in guess
an opinion or judgment based on little or no evidence it's pure supposition on your part that there's something illegal going on next door

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3
as in assumption
something taken as being true or factual and used as a starting point for a course of action or reasoning worthless genetic research that was based on the erroneous supposition that acquired characteristics can be passed on to offspring

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Example Sentences

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.
Recent Examples of supposition 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 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 supposition is the equivalent of green tea giant Bigelow taking Coca-Cola to court for its pour dominance in McDonald’s restaurants. — John Tamny, Forbes.com, 16 Apr. 2026 Zlotnikov wrote that the condition was likely caused by a mutation that had occurred very early in embryonic development, a supposition that was confirmed decades later by genetic analysis. — Jerome Groopman, New Yorker, 6 Apr. 2026 See All Example Sentences for supposition
Recent Examples of Synonyms for supposition
  1. hypothesis
  2. guess
  3. assumption
  4. theory
  5. conjecture
  6. thesis
  7. proposition
Noun
  • Consistent with their hypothesis, the secretion signal helps transfer the enzyme out of the cell, while the lipid anchor holds it near the cell surface.
    — Muskan Bhatia, Interesting Engineering, 21 Oct. 2026
  • But there are indirect consequences of the Many Worlds hypothesis that could lend the idea credibility.
    — Philipp Strasberg, Scientific American, 20 Oct. 2026
Definition of hypothesis
Noun
  • Other guesses had commenters point to The Substance, The Little Mermaid’s Ursula, SpongeBob, and the Demogorgons from Stranger Things.
    — Shania Russell, Entertainment Weekly, 25 Oct. 2026
  • What lurks over the next ridge or the next nightfall is anyone’s guess.
    — Angie Han, HollywoodReporter, 23 Oct. 2026
Definition of guess
Noun
  • The firm also cut its price target to $11 from $13 and raised its fuel expense assumption for the third quarter to about $207 million.
    — Paulina Likos, CNBC, 23 Oct. 2026
  • This assumption is oversimplified, and the problem is partly one of accounting.
    — Ben Vanpeperstraete, Footwear News, 23 Oct. 2026
Definition of assumption
Noun
  • Pike didn’t always have such a cogent theory of the power of the body in performance.
    — Sarah Crompton, Vogue, 21 Oct. 2026
  • The idea that the absence of private property and systematic inequality automatically removes coercion—which forms the core of the Marxist theory of history—is not proven.
    — Literary Hub, Literary Hub, 21 Oct. 2026
Definition of theory
Noun
  • No matter how much Reid would rather talk about anything else — and no matter how much the 23-year-old Simmons’ future remains to be determined despite conjecture through the haze.
    — Kansas City Star, Kansas City Star, 26 Oct. 2026
  • On its surface, the conjecture concerns the behavior of a particular function.
    — Quanta Magazine, Quanta Magazine, 19 Oct. 2026
Definition of conjecture
Noun
  • Michael Monaghan, portfolio manager at Founder ETFs, says that's part of the investment thesis.
    — Jordan Novet, CNBC, 26 Oct. 2026
  • Written in Latin, the theses were relatively tentative in tone, consisting of 95 short propositions—most just a sentence or two.
    — Encyclopedia Britannica, Encyclopedia Britannica, 22 Oct. 2026
Definition of thesis
Noun
  • Populated almost entirely by impossibly wealthy characters reveling in penthouse splendor, the Astaire-Rogers movies argued with high style against the proposition that the material and social rewards of wealth were dubious.
    — David Hajdu, Vanity Fair, 20 Oct. 2026
  • Strong revenue growth, and accelerating demand for our clothes globally, tells us there is a genuine appetite for our British modern luxury proposition.
    — Samantha Conti, Footwear News, 20 Oct. 2026
Definition of proposition

Browse Nearby Words

supposing
supposition
suppositional
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Cite this Entry

“Supposition.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/supposition. Accessed 28 Oct. 2026.

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