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pi·on | \ ˈpī-ˌän 
\
\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 \ adjective
\ adjectiveExamples of pion in a Sentence
Recent Examples on the Web 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.
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Quanta Magazine, "Physicists Uncover Geometric ‘Theory Space’," 23 Feb. 2017 The Xi decays into a particle called the lambda baryon and three lighter particles, the K- (or kaon) and two pions.
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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.
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Adam Mann, WIRED, "Mysterious Subatomic Particle May Represent Exotic New Form of Matter," 17 June 2013
See MoreThese 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.
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Time Traveler for pion
The first known use of pion was in 1950
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