chain reaction


Definition of chain reaction

1a : 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

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Other Words from chain reaction

chain-react \ ˈchān-​rē-​ˈakt How to pronounce chain-react (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

The state party has ignored DNC ultimatums and blown off deadlines to hold new officer elections, setting off a chain reaction that has thrown Alabama’s participation in next year’s presidential primaries up in the air. al, "Is there hope in hell for Alabama Democrats?," 24 Aug. 2019 The danger for Mr Putin now is that the protests will trigger a chain reaction throughout Russia. The Economist, "Protests in Moscow show that Putin’s critics are getting stronger," 15 Aug. 2019 Gauff’s breakout run to the fourth round last month at the All England Club set off a chain reaction of sorts, leading to Baptiste’s upset of world No. Andy Kostka, USA TODAY, "Caty McNally, 17, beats Christina McHale to reach quarterfinals of Citi Open," 1 Aug. 2019 Damage to the carbon fiber liner then propagated and caused it to burst, starting a chain reaction that annihilated the rocket and its payload. Joe Pappalardo, Popular Mechanics, "SpaceX and NASA Reach Agreement on Astronaut Safety," 20 Aug. 2018 That collision—called nuclear fission—releases more neutrons that react with more atoms, creating a chain reaction. National Geographic, "What is nuclear energy and is it a viable resource?," 26 Mar. 2019 In essence, the nerve agent triggers a protein chain reaction, resulting in an uncontrolled bombardment of body tissue and organs with nerve signals by a neurotransmitter called acetylcholine. Deutsche Welle, USA TODAY, "Novichok: What is Russia's dangerous poison used in ex-spy Sergei Skripal's case?," 13 Mar. 2018 Just as a co-worker’s stress can spread to others via late-night emails and terse hallway exchanges, so too can a powerful colleague’s apparent apathy set off a disastrous chain reaction. Sarah Todd, Quartz at Work, "Why it’s so dangerous when star employees check out," 2 July 2019 Their surgeries were performed a day apart in March and that set off a chain reaction. Mola Lenghi, CBS News, "Sisters who donated kidneys set off chain reaction of giving," 2 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'chain reaction.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of chain reaction

circa 1902, in the meaning defined at sense 1a

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Statistics for chain reaction

Last Updated

28 Aug 2019

Look-up Popularity

Time Traveler for chain reaction

The first known use of chain reaction was circa 1902

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More Definitions for chain reaction

chain reaction


English Language Learners Definition of chain reaction

: a series of events in which each event causes the next one : a series of events caused by one single event
technical : a chemical or nuclear change that causes other changes of the same kind to happen

chain reaction


Kids Definition of chain reaction

: a series of events in which each event causes the next one

chain reaction


Medical Definition of chain reaction

: 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 Encyclopedia article about chain reaction

Comments on chain reaction

What made you want to look up chain reaction? Please tell us where you read or heard it (including the quote, if possible).


concealment of treason or felony

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