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.