pi·​on | \ ˈpī-ˌän How to pronounce pion (audio) \

Definition of pion

: a meson that is a combination of up and down quarks and antiquarks, that may be positive, negative, or neutral, and that has a mass about 270 times that of the electron

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Other Words from pion

pionic \ pī-​ˈä-​nik How to pronounce pionic (audio) \ adjective

Examples of pion in a Sentence

Recent Examples on the Web

The Xi decays into a particle called the lambda baryon and three lighter particles, the K- (or kaon) and two pions. Fox News, "‘Charming’ heavy particle discovered at world’s largest atom smasher," 11 July 2017 The most famous of these two-quark particles are kaons and pions. Adam Mann, WIRED, "Mysterious Subatomic Particle May Represent Exotic New Form of Matter," 17 June 2013

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

First Known Use of pion

1950, in the meaning defined above

History and Etymology for pion

contraction of pi-meson

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Dictionary Entries near pion






Pioneer Day

pioneer gold

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Time Traveler for pion

The first known use of pion was in 1950

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Rhyming Dictionary: Words that rhyme with pion

Comments on pion

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something desired as essential

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