Source : Webster's Revised Unabridged Dictionary (1913)

Annihilation \An*ni`hi*la"tion\, n. [Cf. F. annihilation.]
   1. The act of reducing to nothing, or nonexistence; or the
      act of destroying the form or combination of parts under
      which a thing exists, so that the name can no longer be
      applied to it; as, the annihilation of a corporation.

   2. The state of being annihilated. --Hooker.

Source : WordNet®

annihilation
     n 1: destruction by annihilating something [syn: {obliteration}]
     2: total destruction; "bomb tests resulted in the annihilation
        of the atoll" [syn: {disintegration}]