Definition of pion in English:


Line breaks: pion
Pronunciation: /ˈpʌɪɒn


  • A meson having a mass approximately 270 times that of an electron. Also called pi-meson.
    More example sentences
    • The proton and the neutron are baryons; the electron, the muon, and the neutrino are leptons; whilst the pions are mesons.
    • Kaons and pions are examples of particles known as mesons, which contain a quark and an antiquark.
    • He worked primarily on the interaction of pions with protons.



Pronunciation: /pʌɪˈɒnɪk/
More example sentences
  • In other words, the pionic system, having its specific ground state and elementary pionic excitations converts rapidly into free pions.
  • Pionic atoms are exotic systems in which a negatively charged pion is bound in an atom-like orbital.


1950s: from pi1 (the letter used as a symbol for the particle) + -on.

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