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
pionicplay \pī-ˈä-nik\ adjective
Recent Examples of pion from the Web
The most famous of these two-quark particles are kaons and pions.
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Origin and Etymology of pion
contraction of pi-meson
First Known Use: 1950See Words from the same year
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