The Collaborative International Dictionary of English v.0.48:

boson \bo"son\ (b[=o]"z[o^]n), n. [From S. N. Bose, an Indian
   physicist.] (Physics)
   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]

The Collaborative International Dictionary of English v.0.48:

boson \bo"son\ (b[=o]"s'n), n.
   See Boatswain. [Obs.] [Also spelled bosun.] --Dryden.
   [1913 Webster]

WordNet (r) 3.0 (2006):

boson
    n 1: any particle that obeys Bose-Einstein statistics but not
         the Pauli exclusion principle; all nuclei with an even mass
         number are bosons

Hitchcock's Bible Names Dictionary (late 1800's):

Boson, taking away