catalyst

American  

[kat-l-ist] / ˈkæt l ɪst /

noun

1. Chemistry. a substance that causes or accelerates a chemical reaction without itself being affected.

2. something that causes activity between two or more persons or forces without itself being affected.

3. a person or thing that precipitates an event or change.

   His imprisonment by the government served as the catalyst that helped transform social unrest into revolution.

4. a person whose talk, enthusiasm, or energy causes others to be more friendly, enthusiastic, or energetic.

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catalyst British  

/ ˈkætəlɪst /

noun

1. a substance that increases the rate of a chemical reaction without itself suffering any permanent chemical change Compare inhibitor

2. a person or thing that causes a change

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catalyst Scientific  

/ kăt′l-ĭst /

1. A substance that starts or speeds up a chemical reaction while undergoing no permanent change itself. The enzymes in saliva, for example, are catalysts in digestion.

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catalyst Cultural  

1. In chemistry, a substance that causes a chemical reaction to occur but is not itself involved in the reaction.

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Discover More

The term catalyst is often used to refer to the prime agent of any change: “She was the catalyst for the reorganization.”

Other Word Forms

• self-catalyst
  noun
• semicatalyst
  noun

Etymology

Origin of catalyst

First recorded in 1900–05; cataly(sis) + (-i)st

Explanation

A catalyst is an event or person causing a change. Getting kicked out of your parents' house might be a catalyst for becoming more independent. The noun catalyst is something or someone that causes a change and is derived from the Greek word katalύein, meaning "to dissolve." It can be somewhat ordinary, like when moving to a warmer climate was the catalyst for getting a short, sporty haircut. Or it can be major, like how the assassination of Archduke Franz Ferdinand of the Austro-Hungarian Empire is said to be a catalyst of World War I.

Example Sentences

David Miller, CIO and portfolio manager at Catalyst Funds, told MarketWatch that despite the “large tear” Micron’s stock has been on, it’s still trading at under 10-times forward earnings-per-share estimates.

From MarketWatch • May 27, 2026

David Miller, CIO and portfolio manager at Catalyst Funds, told MarketWatch that despite the “large tear” Micron’s stock has been on, it’s still trading at under 10 times forward earnings-per-share estimates.

From MarketWatch • May 27, 2026

“It helps place the city of Los Angeles on a path of ending racial profiling by LAPD,” said Chauncee Smith, of Catalyst California, a group that advocates for racial justice.

From Los Angeles Times • May 6, 2026

Financial markets have appeared overly optimistic in their expectations for the reopening of the strait, Catalyst Energy Infrastructure Fund portfolio manager Simon Lack says in a note.

From The Wall Street Journal • May 4, 2026

I had never heard of this George Prince, though I was familiar with the Federated Catalyst Corporation, of course.

From Brigands of the Moon by Cummings, Ray

Related Words

• impetus
• incentive
• motivation
• stimulant