Dictionary
grav•i•ton
Pronunciation: (grav'i-ton"), [key]—
n. Physics.
the theoretical quantum of gravitation, usually assumed to be an elementary particle that is its own antiparticle and that has zero rest mass and charge and a spin of two. Cf.
photon.Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.