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

Example Sentences

Recent Examples on the Web 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

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tachyon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


tachy- + -on entry 2

First Known Use

1967, in the meaning defined above

Time Traveler
The first known use of tachyon was in 1967

Dictionary Entries Near tachyon

Cite this Entry

“Tachyon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tachyon. Accessed 5 Feb. 2023.

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