Yours, Etc.: Origins and Uses of 8 Sign-Offs
subatomic particle n.
Any of various units of matter below the size of an atom, including the elementary particles and hadrons.
subatomic particle |
Any of various particles of matter that are smaller than a hydrogen atom. Protons, neutrons, and electrons are subatomic particles, as are all hadrons and leptons. See also composite particle, elementary particle.