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

Other Words from pion

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

Examples of pion in a Sentence

Recent Examples on the Web When a very fast pion crashes into a hydrogen atom, the energy held within this force is released all at once, similar to a snapping rubber band. Elizabeth Fernandez, Forbes, 19 Sep. 2021 In 2019, Alberg and Miller calculated what SeaQuest should observe based on the pion cloud idea. Quanta Magazine, 24 Feb. 2021 An early triumph in which Chew’s students used the bootstrap to predict the mass of the rho meson — a particle made of pions that are held together by exchanging rho mesons — won many converts. Quanta Magazine, 23 Feb. 2017 The Xi decays into a particle called the lambda baryon and three lighter particles, the K- (or kaon) and two pions. Fox News, 11 July 2017 The most famous of these two-quark particles are kaons and pions. Adam Mann, WIRED, 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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Cite this Entry

“Pion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pion. Accessed 11 Aug. 2022.

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