chain reaction

noun

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 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.
Then the Pavia ruling changed everything, setting off the chain reaction that led Aguilar from Boone to Los Angeles, then back east to Knoxville. Sam Khan Jr, New York Times, 25 July 2025 The conference will take place near the campus location where Fermi oversaw the first self-sustaining nuclear chain reaction in the run-up to that fateful July 16 bomb test. The Editorial Board, Chicago Tribune, 14 July 2025 Uranium enrichment involves removing uranium-238 and increasing the proportion of uranium-235, which supports the fission chain reaction needed for nuclear power and weapons. Brendan Cole, MSNBC Newsweek, 25 June 2025 Cole is Brad Vinick, a successful businessman whose sizable donation to his alma mater starts a chain reaction that leads to Charles getting hired. Denise Petski, Deadline, 6 May 2025 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

Browse Nearby Words

Cite this Entry

“Chain reaction.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/chain%20reaction. Accessed 29 Jul. 2025.

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

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