the act or an instance of annihilating.

the state of being annihilated; extinction; destruction.

Physics .

Also called pair annihilation. the process in which a particle and antiparticle unite, annihilate each other, and produce one or more photons. Compare positronium .

the conversion of rest mass into energy in the form of electromagnetic radiation.

noun

eradication , extermination , extinction , extinguishment , extirpation , liquidation , obliteration , abolishment , abrogation , annulment , cancellation , defeasance , invalidation , negation , nullification , voidance