the·​o·​rem | \ˈthē-ə-rəm, ˈthir-əm\

Definition of theorem 

1 : a formula, proposition, or statement in mathematics or logic deduced or to be deduced from other formulas or propositions

2 : an idea accepted or proposed as a demonstrable truth often as a part of a general theory : proposition the theorem that the best defense is offense

3 : stencil

4 : a painting produced especially on velvet by the use of stencils for each color

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Other Words from theorem

theorematic \ˌthē-​ə-​rə-​ˈma-​tik, ˌthir-​ə-​ \ adjective

Examples of theorem in a Sentence

Recent Examples on the Web

The problem came to be called the ultraviolet catastrophe, because the best theorem of the day predicted that objects heated to very high temperatures should spew infinite amounts of short-wavelength energy. Tim Folger, Discover Magazine, "How Quantum Mechanics Lets Us See, Smell and Touch," 24 Oct. 2018 The prime number theorem and Riemann hypothesis get the attention and the money, but both followed up on earlier, less glamorous data analysis. ..... Martin H. Weissman, Smithsonian, "Why Prime Numbers Still Surprise and Mystify Mathematicians," 2 Apr. 2018 To understand their thinking, consider that classic political science concept: the median voter theorem. Andrew Prokop, Vox, "The top-two primary could lock out Democrats from key House races.," 5 June 2018 Stonehenge secret: Did builders use Pythagoras' theorem 2,000 years before the philosopher lived? Fox News, "FOX NEWS FIRST: Remembering Charles Krauthammer; Melania's fashion 'statement' sparks 'fake news' frenzy," 22 June 2018 His theorem, a part of Euclidean geometry taught in many high school math classes, states that the hypotenuse of a right triangle (the side opposite the right angle) equals the sum of the squares of the other two sides. Kevin Kelleher, Fortune, "Stonehenge Builders Used Pythagoras' Theorem Centuries Before His Birth, Say Experts," 21 June 2018 Similarly, the ubiquitous use of Bayesian statistics in scientific areas has enticed philosophers to go back to Bayes’ theorem and to unpack its problems and prospects. Philip Ball, WIRED, "Questioning Truth, Reality, and the Role of Scientific Progress," 2 June 2018 Miller concocted his theorem to explain why state Rep. Ken Dunkin, a Democrat, got whooped, while state Senator Sam McCann, a Republican, was reelected in the March 2016 primaries. Ben Joravsky, Chicago Reader, "News / Politics How Dems in red states can fight off Trump's vicious attacks," 31 May 2018 Another was a problem cracked in the 1990s by British number theorist Andrew Wiles and a coauthor: that work led them to solve Fermat’s last theorem, earning Wiles the Abel Prize in 2016. Davide Castelvecchi, Scientific American, "“Grand Unified Theory of Math” Nets Abel Prize," 20 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'theorem.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of theorem

1551, in the meaning defined at sense 1

History and Etymology for theorem

Late Latin theorema, from Greek theōrēma, from theōrein to look at, from theōros spectator, from thea act of seeing — more at theater entry 1

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Statistics for theorem

Last Updated

7 Dec 2018

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Time Traveler for theorem

The first known use of theorem was in 1551

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English Language Learners Definition of theorem

: a formula or statement that can be proved from other formulas or statements

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Rhyming Dictionary: Words that rhyme with theorem

Spanish Central: Translation of theorem

Nglish: Translation of theorem for Spanish Speakers Encyclopedia article about theorem

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What made you want to look up theorem? Please tell us where you read or heard it (including the quote, if possible).


the figure or shape of a crescent moon

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