: 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
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Treatment protocols here are made-to-measure and use the brand’s products, which are created with bio-fermentation, enzymatic catalysis and plant cell culture technologies. Lily Templeton, WWD, 27 Jan. 2025 Related Stories This isn’t a novel concept; carbon-to-cellulose can be accomplished through traditional processes like fermentation or chemical catalysis. Alexandra Harrell, Sourcing Journal, 3 Sep. 2019

Word History

Etymology

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

First Known Use

1836, in the meaning defined above

Time Traveler
The first known use of catalysis was in 1836

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Cite this Entry

“Catalysis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/catalysis. Accessed 27 Jul. 2025.

Kids Definition

catalysis

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

Medical Definition

catalysis

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

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