spall·​ation spȯ-ˈlā-shən How to pronounce spallation (audio)
: a nuclear reaction in which light particles are ejected as the result of bombardment (as by high-energy protons)
: the process of spalling

Example Sentences

Recent Examples on the Web Are there a sufficient number of meteorites slamming into planets to launch life-seeding rocks through space (a.k.a. cause spallation)? Carl Engelking, Discover Magazine, 13 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'spallation.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1947, in the meaning defined at sense 1

Time Traveler
The first known use of spallation was in 1947

Dictionary Entries Near spallation

Cite this Entry

“Spallation.” Dictionary, Merriam-Webster, Accessed 30 Mar. 2023.

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