catalyst

noun

cat·​a·​lyst ˈka-tə-ləst How to pronounce catalyst (audio)
1
: a substance that enables a chemical reaction to proceed at a usually faster rate or under different conditions (as at a lower temperature) than otherwise possible
2
: an agent that provokes or speeds significant change or action
That waterway became the catalyst of the area's industrialization.
He was the catalyst in the native uprising.

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Word History of Catalyst

Catalyst is a fairly recent addition to the English language, first appearing at the start of the 20th century with its chemistry meaning. It was formed from the word catalysis, another chemistry term which refers to a modification and especially an increase in the rate of a chemical reaction induced by material unchanged chemically at the end of the reaction. By the 1940s, the figurative sense of catalyst was in use for someone or something that quickly causes change or action.

Examples of catalyst in a Sentence

The bombing attack was the catalyst for war. She was proud to be a catalyst for reform in the government.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Singer Cassie, Diddy’s ex-girlfriend whose real name is Casandra Elizabeth Ventura, was the catalyst to Diddy’s legal woes. Grethel Aguila, Miami Herald, 3 Oct. 2025 Jim is betting on the latter and is confident that this is the catalyst Texas Roadhouse needs. Natasha Abellard, CNBC, 3 Oct. 2025 Many drugs, enzymes, catalysts, and other chemicals of incalculable value were first identified in natural samples. IEEE Spectrum, 2 Oct. 2025 The availability of Bradley Beal was the catalyst, but Collins gives the Clippers a different dimension. John Hollinger, New York Times, 1 Oct. 2025 See All Example Sentences for catalyst

Word History

Etymology

see catalysis

First Known Use

1902, in the meaning defined at sense 1

Time Traveler
The first known use of catalyst was in 1902

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Cite this Entry

“Catalyst.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/catalyst. Accessed 8 Oct. 2025.

Kids Definition

catalyst

noun
cat·​a·​lyst ˈkat-ᵊl-əst How to pronounce catalyst (audio)
1
: a substance that changes the rate of a chemical reaction but is itself unchanged at the end of the process
especially : such a substance that speeds up a reaction or enables it to proceed under milder conditions
2
: a person or event that quickly causes change or action
the scandal was a catalyst for reform

Medical Definition

catalyst

noun
cat·​a·​lyst ˈkat-ᵊl-əst How to pronounce catalyst (audio)
: a substance (as an enzyme) that enables a chemical reaction to proceed at a usually faster rate or under different conditions (as at a lower temperature) than otherwise possible
Last Updated: - Updated example sentences
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