ca·​tal·​y·​sis | \ kə-ˈta-lə-səs How to pronounce catalysis (audio) \
plural catalyses\ kə-​ˈta-​lə-​ˌsēz How to pronounce catalyses (audio) \

Definition of catalysis

: a modification and especially increase in the rate of a chemical reaction induced by material unchanged chemically at the end of the reaction

Examples of catalysis in a Sentence

Recent Examples on the Web At the surface Where the SrTiO3 tends to fall short is in the catalysis. John Timmer, Ars Technica, "New material releases hydrogen from water at near-perfect efficiency," 27 May 2020 That crystalline structure imparts mechanical properties that are useful for catalysis, gas storage, and drug delivery, for example. Jennifer Ouellette, Ars Technica, "Watch this paper doll do sit-ups thanks to new kind of “artificial muscle”," 21 July 2019

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

First Known Use of catalysis

1836, in the meaning defined above

History and Etymology for catalysis

Greek katalysis dissolution, from katalyein to dissolve, from kata- + lyein to dissolve, release — more at lose

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Time Traveler for catalysis

Time Traveler

The first known use of catalysis was in 1836

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Cite this Entry

“Catalysis.” Dictionary, Merriam-Webster, Accessed 29 Sep. 2020.

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More Definitions for catalysis


ca·​tal·​y·​sis | \ kə-ˈtal-ə-səs How to pronounce catalysis (audio) \
plural catalyses\ -​ˌsēz How to pronounce catalyses (audio) \

Medical Definition of catalysis

: a change and especially increase in the rate of a chemical reaction induced by a catalyst

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