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

When grounded in spiritual values, this mindset creates a self-sustaining ecosystem of generosity, where hope grows and every challenge becomes a catalyst for deeper impact. Nonprofits can no longer rely solely on spreadsheets and fundraising targets to sustain their missions. —Yujia Zhu, Forbes.com, 8 Aug. 2025

Their separation served as the catalyst for Clarkson's 10th studio album, Chemistry, released in 2023. —EW.com, 7 Aug. 2025

Smith and Christian’s respective grandfathers were their catalysts into vintage fashion. —Angela Velasquez, Footwear News, 6 Aug. 2025

This connection would be the catalyst for his debut feature, the migrant drama The Sand Castle, which was revealed by Netflix last month as being the platform’s most watched Arabic-language movie in the first six months of 2025, garnering 10.8M views and 17.4M hours watched by a wide margin. —Melanie Goodfellow, Deadline, 4 Aug. 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