ax·​i·​om | \ ˈak-sē-əm How to pronounce axiom (audio) \

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

The former sees liberalism as a set of axioms that were discovered during the Enlightenment and that should govern all of human life. Ramesh Ponnuru, National Review, "The Right Liberalism," 11 July 2019 The distilled essence of today’s Republicanism is denial of the axiom that there are just two ways to finance government — contemporary taxes or future taxes. George Will, Twin Cities, "George Will: The repeal of the ‘Cadillac tax’ showed a hazard of bipartisanship," 25 July 2019 Normatively, the axiom is understood to relate to many ventures. Rabbi Avi Weiss,, "Apparent temporary situations can become true tests of resolve," 24 June 2019 Hilbert’s sixth problem called upon researchers to axiomatize the laws of physics — that is, rigorously construct them from a basic set of starting assumptions, or axioms. Quanta Magazine, "Famous Fluid Equations Are Incomplete," 21 July 2015 The fact that some fathers, like Jefferson and the GIs, have remained strategically uncertain suggests the very notion of paternal uncertainty is not a biological axiom but a political idea. The Conversation,, "Who’s is your daddy? It’s not all about DNA," 16 June 2019 Yet a federal judge last week divined an exception to this constitutional axiom by enshrining a Barack Obama order walling off 128 million acres of the Arctic and eastern seaboard from oil and gas production. The Editorial Board, WSJ, "Entrenching the Obama Presidency," 5 Apr. 2019 There’s no specification of what kind of underlying physical reality gives rise to these axioms. Quanta Magazine, "Mysterious Quantum Rule Reconstructed From Scratch," 13 Feb. 2019 The problem is that Moore’s Law, the axiom that transistors double over two years, has slowed, putting a premium on design. Mark Hachman, PCWorld, "AMD announces 3rd-gen Ryzen and Radeon VII, beating Intel and Nvidia to 7nm," 9 Jan. 2019

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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Last Updated

20 Aug 2019

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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 How to pronounce axiom (audio) \

Kids Definition of axiom

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

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More from Merriam-Webster on axiom

Thesaurus: All synonyms and antonyms for axiom

Spanish Central: Translation of axiom

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

Comments on axiom

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


not constant or steady

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