ax·​ion | \ ˈak-sē-(ˌ)än How to pronounce axion (audio) \

Definition of axion

: a hypothetical subatomic particle of low mass and energy that is postulated to exist because of certain properties of the strong force

Examples of axion in a Sentence

Recent Examples on the Web Wilczek came up with the theory in 1987 to describe how a hypothetical particle called an axion would interact with electricity and magnetism. Quanta Magazine, "‘Quantum Atmospheres’ May Reveal Secrets of Matter," 25 Sep. 2018 Enter the axion, the second-most promising candidate for dark matter. Jennifer Ouellette, Ars Technica, "Physicists propose listening for dark matter with plasma-based “axion radio”," 17 Oct. 2019 Then there are theorized particles like SIMPs and axions—and countless other potential clues. Joe Lindsey, Popular Mechanics, "Filling the Void: What Is Dark Matter?," 28 May 2019 However, neutron stars may provide a sort of amplification, making axions visible. Chris Lee, Ars Technica, "Pulsars could convert dark matter into something we could see," 20 Dec. 2018 The hunt for wispy particles called axions, which might make up the dark matter whose gravity keeps galaxies from falling apart, is heating up. Adrian Cho, Science | AAAS, "Search for superlight dark matter particles heats up," 9 Apr. 2018 Or hypothesized particles called axions that interact with magnetic fields might be detected in laboratories or in space. Lisa Randall, Scientific American, "What Is Dark Matter?," 8 May 2018

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

1978, in the meaning defined above

History and Etymology for axion

axial + -on entry 2

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Time Traveler for axion

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The first known use of axion was in 1978

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Last Updated

29 Nov 2019

Cite this Entry

“Axion.” The Dictionary, Merriam-Webster Inc., Accessed 7 December 2019.

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