tachy·​on | \ˈta-kē-ˌän \

Definition of tachyon 

: a hypothetical particle held to travel faster than light

Examples of tachyon in a Sentence

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, "Was This Stephen Hawking's Theory of Everything?," 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.

First Known Use of tachyon

1967, in the meaning defined above

History and Etymology for tachyon

tachy- + -on entry 2

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Time Traveler for tachyon

The first known use of tachyon was in 1967

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More from Merriam-Webster on tachyon

See words that rhyme with tachyon

Britannica English: Translation of tachyon for Arabic Speakers

Britannica.com: Encyclopedia article about tachyon

Comments on tachyon

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playful or foolish behavior

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