D defs.my
Entry 1 sense Webster, 1913

mu-meson

· IPA
01 n. an elementary particle with a negative charge and a half-life of 2 microseconds; the muon. It is a lepton, not a true meson, and decays to…
  1. 1.
    an elementary particle with a negative charge and a half-life of 2 microseconds; the muon. It is a lepton, not a true meson, and decays to an electron and neutrino and antineutrino.(Physics)
Syn. muon, negative muon.