SUPPOSITION Synonyms: 70 Similar and Opposite Words

supposition

noun

ˌsə-pə-ˈzi-shən

Definition of supposition

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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Antonyms & Near Antonyms

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

Synonyms & Similar Words

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

Synonyms & Similar Words

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

Noun

Among the results claimed are a solution to the four-dimensional Kakeya conjecture, improvements on some of the world’s most important computer algorithms, and actual progress toward math’s scariest problem, the Riemann hypothesis.

— Joseph Howlett, Scientific American, 6 Oct. 2026
The corroded terminal, the location, 30 seconds of video of the noise, the hypothesis that was ruled out.

— Julien Vantyghem, Forbes.com, 5 Oct. 2026

Definition of hypothesis

Noun

Russia’s invasion of Ukraine ended the assumption that energy infrastructure could be insulated from geopolitics.

— Sam Birchall, Fortune, 2 Oct. 2026
Zahir Islam, PhD, a physicist at ANL, and co-author of the study, said the finding challenges a common assumption in microelectronics that the substrate beneath a thin film simply acts as a passive support.

— Georgina Jedikovska, Interesting Engineering, 2 Oct. 2026

Definition of assumption

Noun

Some universities have a long standing tradition of continually testing students’ ability to explain and rationalise their theories.

— Reynald Fasciaux, Fortune, 8 Oct. 2026
The defense said the government’s theory is unsupported and urged the judge to dismiss the charges.

— Kaelan Deese, The Washington Examiner, 7 Oct. 2026

Definition of theory

Noun

Many mathematicians have stopped posting open conjectures and potential ideas at the end of their papers, for fear that they’ll be scraped by bots and fed into AI models.

— Jordana Cepelewicz, Quanta Magazine, 5 Oct. 2026
The lonely runner conjecture predicts that, at some point, a runner will be maximally distant from all the other runners—the saddest, loneliest phase of the race.

— Lyndie Chiou, Scientific American, 2 Oct. 2026

Definition of conjecture

Noun

Jackson gives you a whole clan of old-money Brooklyn Heights Stocktons, but the character who carries the thesis is Sasha, the middle-class New England girl who marries in and is instantly, permanently cast as the arriviste.

— Literary Hub, Literary Hub, 5 Oct. 2026
Ability to flex pricing power The crown jewel of Applied Aerospace’s investment thesis lies in its 87% single-source contract mix.

— Harvey Stober, CNBC, 2 Oct. 2026

Definition of thesis

Noun

Travel retail is no longer a price-value proposition that competes just with the high street, but also with platforms such as Amazon, Rakuten and Tmall around the globe.

— Jennifer Weil, Footwear News, 6 Oct. 2026
Eco effort Inkaterra's core proposition is a care and value for the environment—trust that your stay is built to have a small (negative, even) carbon footprint, with efforts that go far beyond encouraging you to reuse a towel.

— Condé Nast, Condé Nast Traveler, 6 Oct. 2026

Definition of proposition

Browse Nearby Words

supposing

supposition

suppositional

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Style

“Supposition.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/supposition. Accessed 10 Oct. 2026.

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Synonyms of supposition

noun

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