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.
Whatever Broward Circuit Judge Carlos Rodriguez decides would set off a chain reaction, with the fate of the Sheriff’s Office’s relationship to Deerfield Beach hanging in the balance. — Rafael Olmeda, Sun Sentinel, 15 Aug. 2026 Thermal runaway occurs when a single failing cell overheats and triggers a chain reaction across an entire battery pack. — Mrigakshi Dixit, Interesting Engineering, 10 Aug. 2026 Every two to seven years, sea surface temperatures in the eastern and central Pacific Ocean along the equator rise well above normal, setting off a chain reaction that reshapes weather patterns around the globe. — Sean MacAday, Sacbee.com, 6 Aug. 2026 That followed a March 2024 fatal accident in which Bain hit another car on I-95 in South Florida, setting off a chain reaction accident that eventually left one of his passengers non-responsive. — Armando Salguero, FOXNews.com, 30 July 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
See all Nearby Words

Cite this Entry

“Chain reaction.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/chain%20reaction. Accessed 18 Aug. 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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