an·​ni·​hi·​la·​tion | \ ə-ˌnī-ə-ˈlā-shən How to pronounce annihilation (audio) \
plural annihilations

Definition of annihilation

1 : the state or fact of being completely destroyed or obliterated : the act of annihilating something or the state of being annihilated The late 1940s and '50s were so pervaded by a general fear of nuclear annihilation that the era was known as the Age of Anxiety.— Charles Krauthammer For a literary culture that fears it is on the brink of total annihilation, we are awfully cavalier about the Great Male Novelists of the last century.— Katie Roiphe … few experts believe that either regime would risk annihilation by actually launching a nuke in anger.— Michael Elliott The Cretaceous Extinction, whatever its cause, was one of the two most awesome annihilations of life in the history of the world.— John McPhee
2 physics : the combination of a particle and its antiparticle (such as an electron and a positron) that results in the subsequent total conversion of the particles into energy Both the creation and annihilation of antimatter have been observed in nuclear accelerators (atom-smashers).— Harding E. Smith The annihilation reactions are the most efficient sources of energy known, for in them the entire mass of both particles is converted into pure energy.— George Greenstein

First Known Use of annihilation

1585, in the meaning defined at sense 1

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The first known use of annihilation was in 1585

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Cite this Entry

“Annihilation.” Dictionary, Merriam-Webster, Accessed 20 Jan. 2021.

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