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 Other axion searches use our sun, which is expected to produce axions in its interior that then stream into space. Quanta Magazine, 19 Oct. 2021 Physicists suspect that this signals the existence of a new kind of particle—the axion—that formed in the early universe and has the right properties to be dark matter. Priyamvada Natarajan, The New York Review of Books, 15 June 2021 Wilczek is enthusiastic about the many experimental efforts currently underway to detect the axion. Priyamvada Natarajan, The New York Review of Books, 15 June 2021 The Sun could be producing a novel type of (candidate dark matter) particle known as an axion. Ethan Siegel, Forbes, 27 Apr. 2021 Live Science shared the XENON collaboration’s press release with two axion experts. Rafi Letzter, Scientific American, 17 June 2020 This is the shape of the mathematical function defining the axion field. Quanta Magazine, 17 Mar. 2020 The new idea, which goes by the name axiogenesis, could further motivate experimental searches for the axion. Quanta Magazine, 17 Mar. 2020 To demonstrate their idea, Jiang and Wilczek focused on an unorthodox set of rules called axion electrodynamics, which could give rise to unique properties. Quanta Magazine, 25 Sep. 2018 See More

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.

First Known Use of axion

1978, in the meaning defined above

History and Etymology for axion

axi(al) + -on entry 2

Note: The name axion was introduced by the American physicist Stephen Weinberg (born 1933) in "A New Light Boson?", Physical Review Letters, vol. 40, no. 4 (January 23, 1978), p. 233; and by American physicist Frank Wilczek (born 1951) in "Problems of Strong P and T Invariance in the Presence of Instantons," Physical Review Letters, vol. 40, no. 5, p. 279. In an article in the online journal Quanta, "Time's (Almost) Irreversible Arrow" (January 7, 2016), Frank Wilczek explained the coinage as follows: "A few years before [in 1977], a supermarket display of brightly colored boxes of a laundry detergent named Axion had caught my eye. It occurred to me that 'axion' sounded like the name of a particle and really ought to be one. So when I noticed a new particle that 'cleaned up' a problem with an 'axial' current, I saw my chance. (I soon learned that Steven Weinberg had also noticed this particle, independently. He had been calling it the 'Higglet.' He graciously, and I think wisely, agreed to abandon that name.) Thus began a saga whose conclusion remains to be written."

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axiom system



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Cite this Entry

“Axion.” Dictionary, Merriam-Webster, Accessed 3 Jul. 2022.

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