A fundamental particle that obeys Bose-Einstein statistical rules, but not the Pauli exclusion principle; the spin value of a boson is always an integer. Examples of bosons are alpha particles, photons, and those nuclei which have an even mass number. [PJC]
, n. Physics any of several elementary particles obeying the relations stated by Bose and Einstein, with a zero or integral spin, e.g. photons (cf. FERMION).