An Etymological Dictionary of Astronomy and Astrophysics

Any elementary particle which experiences the strong nuclear force. There are two sorts of hadrons: mesons, which have zero spin, and baryons, which have spin 1/2 or 3/2.

See also: Hadron, from Gk. hadr(os) “thick, bulky” + -on a suffix used in the names of subatomic particles (gluon, meson, neutron), quanta (photon, graviton), and other minimal entities or components (magneton).