ax·​i·​om | \ ˈak-sē-əm \

Definition of axiom

1 : a statement accepted as true as the basis for argument or inference : postulate sense 1 one of the axioms of the theory of evolution
2 : an established rule or principle or a self-evident truth cites the axiom "no one gives what he does not have"
3 : a maxim widely accepted on its intrinsic merit the axioms of wisdom

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Did You Know?

In mathematics or logic, an axiom is an unprovable rule or first principle accepted as true because it is self-evident or particularly useful. “Nothing can both be and not be at the same time and in the same respect” is an example of an axiom. The term is often used interchangeably with postulate, though the latter term is sometimes reserved for mathematical applications (such as the postulates of Euclidean geometry). It should be contrasted with a theorem, which requires a rigorous proof.

Examples of axiom in a Sentence

one of the key axioms of the theory of evolution

Recent Examples on the Web

While the lightning rift has turned into a cube now, the axiom remains true. Patricia Hernandez, The Verge, "Fortnite’s best moments are being ruined by in-game murder," 25 Aug. 2018 That axiom has not been true for some time – at least since Vietnam. Chris Stirewalt, Fox News, "Midterms will mold Dems' 2020 field," 19 July 2018 The worst passages in Mr. Norman’s very good book, that is, come from accepting the axiom that markets are highly imperfect yet easily corrected—and that government, implicitly assumed to be capable of such delicate corrections, should step in. Deirdre Mccloskey, WSJ, "‘Adam Smith: Father of Economics’ Review: Obvious, Simple and Wise," 7 Sep. 2018 For years, China has defied the axiom that a free political system and economic growth go hand in hand. New York Times, "ZTE’s Near-Collapse May Be China’s Sputnik Moment," 10 June 2018 Buy Photo All immigration lawyers know the axiom: Handling deportation cases in immigration court is akin to trying death penalty cases in traffic court. Jonathan Lai,, "Most immigrants facing deportation don't have lawyers. N.J. is changing that," 3 July 2018 The mindless movie taps into a great military axiom: Don‘t prepare to fight the last war, prepare to fight the next one. Joe Pappalardo, Popular Mechanics, "5 Space Forces From Sci-Fi and What We Can Learn From Them," 6 July 2018 Another one of Leonard’s writing axioms was the timeless advice of show, don’t tell. Erik Spanberg, The Christian Science Monitor, "'Elmore Leonard: Westerns' celebrates Leonard's mastery of the genre," 5 June 2018 To paraphrase an old air travel axiom: What goes in must come out, one way or another. Avi Selk, Washington Post, "‘He’s peeing!’: A man’s grabby hands were just the start of this plane nightmare, FBI says," 21 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'axiom.' 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 axiom

15th century, in the meaning defined at sense 3

History and Etymology for axiom

Latin axioma, from Greek axiōma, literally, something worthy, from axioun to think worthy, from axios worth, worthy; akin to Greek agein to weigh, drive — more at agent

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Statistics for axiom

Last Updated

24 Dec 2018

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Time Traveler for axiom

The first known use of axiom was in the 15th century

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More Definitions for axiom


ax·​i·​om | \ ˈak-sē-əm \

Kids Definition of axiom

1 : maxim
2 : a statement thought to be clearly true

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More from Merriam-Webster on axiom

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Britannica English: Translation of axiom for Arabic Speakers Encyclopedia article about axiom

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