chain reaction

noun

Synonyms of chain reactionnext
1
a
: a series of events so related to each other that each one initiates the next
b
: a number of events triggered by the same initial event
2
: a self-sustaining chemical or nuclear reaction yielding energy or products that cause further reactions of the same kind
chain-react
ˈchān-rē-ˈakt How to pronounce chain reaction (audio)
intransitive verb

Examples of chain reaction in a Sentence

Increased oil prices could trigger a chain reaction in the economy.
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.
The five-phase program will begin with initial criticality, the point at which a reactor achieves a self-sustaining nuclear chain reaction. — Neetika Walter, Interesting Engineering, 30 Oct. 2026 Typically, a puncture can trigger a dangerous chain reaction in a lithium-ion battery, leading it to catch fire or explode. — Michael Kan, PC Magazine, 26 Oct. 2026 Scientists call this potential chain reaction the Kessler syndrome. — Kurt Knutsson, FOXNews.com, 25 Oct. 2026 Her toddler vomited, which started a chain reaction of vomit. — Joey Nolfi, Entertainment Weekly, 19 Oct. 2026 See All Example Sentences for chain reaction

Word History

First Known Use

1892, in the meaning defined at sense 1a

Time Traveler
The first known use of chain reaction was in 1892

Rhymes for chain reaction

See All Rhymes for chain reaction

Browse Nearby Words

chain-reacting pile
chain reaction
chain reactor
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Cite this Entry

“Chain reaction.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/chain%20reaction. Accessed 1 Nov. 2026.

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Kids Definition

chain reaction

noun
1
: a series of events so related to each other that each one sets the next one going
2
: a chemical or nuclear reaction producing energy or products that cause further reactions of the same kind

Medical Definition

chain reaction

noun
: a self-sustaining chemical or nuclear reaction yielding energy or products that cause further reactions of the same kind

More from Merriam-Webster on chain reaction

Thesaurus: All synonyms and antonyms for chain reaction

Britannica.com: Encyclopedia article about chain reaction

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