annihilation

UK:**UK and possibly other pronunciationsUK and possibly other pronunciations/əˌnaɪɪˈleɪʃən/US:USA pronunciation: respellingUSA pronunciation: respelling(ə nī′ə lāshən)


WordReference Random House Unabridged Dictionary of American English © 2026
an•ni•hi•la•tion  (ə nī′ə lāshən),USA pronunciation n. 
  1. the act or an instance of annihilating.
  2. the state of being annihilated;
    extinction;
    destruction.
  3. Physics
    • Also called pair annihilation. the process in which a particle and antiparticle unite, annihilate each other, and produce one or more photons. Cf. positronium.
    • the conversion of rest mass into energy in the form of electromagnetic radiation.
  • Late Latin annihilātiōn- (stem of annihilātiō). See annihilate, -ion
  • French)
  • (1630–40

Collins Concise English Dictionary © HarperCollins Publishers::
annihilation /əˌnaɪəˈleɪʃən/ n
  1. total destruction
  2. the act of annihilating
  3. the destruction of a particle and its antiparticle when they collide. The annihilation of an electron with a positron generates two or, very rarely, three photons of annihilation radiation. The annihilation of a nucleon with its antiparticle generates several pions
'annihilation' also found in these entries (note: many are not synonyms or translations):

🗣️Forum discussions with the word(s) "annihilation" in the title:


Look up "annihilation" at Merriam-Webster
Look up "annihilation" at dictionary.com
  • Go to Preferences page and choose from different actions for taps or mouse clicks.

In other languages: Spanish | French | Italian | Portuguese | Romanian | German | Dutch | Swedish | Russian | Polish | Czech | Greek | Turkish | Chinese | Japanese | Korean | Arabic

Advertisements
Advertisements
Report an inappropriate ad.
WordReference.com
WORD OF THE DAY
GET THE DAILY EMAIL!