catalyst

noun

cat·​a·​lyst ˈka-tə-ləst 

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 20^th 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

Tony & Ziva viewers possibly predict that a child’s bed-wetting would be the catalyst for the couple’s June 2020 engagement? —Ryan Schwartz, TVLine, 12 Sep. 2025

His killing could become not just a tragedy but a catalyst—an event that radicalizes ever more Americans, less an aberration than a feature of our increasingly perilous national politics. —Eric Cortellessa, Time, 11 Sep. 2025

Luria cited the growth in AI compute demand as a strong catalyst, and one that could likely sustain Nvidia’s growth into the next year and beyond. —Lisa Kailai Han, CNBC, 11 Sep. 2025

The catalyst wasn’t a flashy product rollout or a surprise earnings beat — in fact, Oracle’s quarterly revenue and profit came in below Wall Street’s expectations Tuesday evening. —Allison Morrow, CNN Money, 11 Sep. 2025

Word History

Etymology

see catalysis

First Known Use

1902, in the meaning defined at sense 1

Phrases Containing catalyst

• co-catalyst

Rhymes for catalyst

• catalysed

Kids Definition

catalyst

noun

cat·​a·​lyst ˈkat-ᵊl-əst 

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 

: 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