tachyon

noun

tachy·​on ˈta-kē-ˌän How to pronounce tachyon (audio)
: a hypothetical particle held to travel faster than light

Examples of tachyon in a Sentence

Recent Examples on the Web
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Yes, there is a hypothetical particle, called the tachyon, that could travel back in time. Paul M. Sutter, Discover Magazine, 21 Feb. 2023 The tachyon particle has an intriguing time travel component. Tim Newcomb, Popular Mechanics, 21 Feb. 2023 The introduction of supersymmetry also solved the nasty problem of tachyons by replacing those troublesome particles with supersymmetric partners, which was a nice flourish. Paul Sutter, Ars Technica, 27 Jan. 2023 This predicts that every particle has a superpartner and, by an extraordinary coincidence, the same condition actually eliminates the tachyon. Lorenzo Bianchi, Newsweek, 19 Mar. 2018

Word History

Etymology

tachy- + -on entry 2

First Known Use

1967, in the meaning defined above

Time Traveler
The first known use of tachyon was in 1967

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Cite this Entry

“Tachyon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tachyon. Accessed 6 Jul. 2026.

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