An Etymological Dictionary of Astronomy and Astrophysics

Any of the class of the heaviest → subatomic particles that includes → protons, → neutrons, as well as a number of short-lived particles whose decay products include protons. Baryons obey the → Fermi-Dirac statistics. They form a subclass of the → hadrons and
are further subdivided into → nucleons and → hyperons.

See also: Gk. barys “heavy” + → -on, from “fermion.”