me·son / ˈmezˌän; ˈmāˌzän; ˈmēˌzän/ • n. Physics a subatomic particle that is intermediate in mass between an electron and a proton and transmits the strong interaction that binds nucleons together in the atomic nucleus.DERIVATIVES: me·son·ic / meˈzänik; mā-; mē-/ adj.

meson Subatomic particle, member of a subgroup of hadrons, all of which have either zero or integral spin. They include the pions, kaons, and eta mesons.