antimatter

English Thesaurus

1. matter consisting of elementary particles that are the antiparticles of those making up normal substances (noun.substance)

hypernym	:	matter,
definition	:	that which has mass and occupies space (noun.tops)

substance holonym	:	antiparticle,
definition	:	a particle that has the same mass as another particle but has opposite values for its other properties; interaction of a particle and its antiparticle results in annihilation and the production of radiant energy (noun.object)