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.
The difference this time is the chain reaction. Vitalii Savryha, Sourcing Journal, 21 Oct. 2025 Second, the flowing glacier brings more ice forward to replace what breaks off, slowing the cliff’s inland retreat and making a chain reaction of cliff toppling less likely. Evan Howell, Quanta Magazine, 20 Oct. 2025 The error within that update then caused a chain reaction of service failures and disruptions. Jaclyn Diaz, NPR, 20 Oct. 2025 If enough satellites are in orbit, this debris could set off a chain reaction, rendering the environment around Earth practically impassable. Big Think, 15 Oct. 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 23 Oct. 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

Last Updated: - Updated example sentences
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