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

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 Sepsis, a medical emergency, occurs when an existing infection triggers an extreme response and chain reaction throughout the body, possibly leading to tissue damage, organ failure and death. Susan Scutti, CNN, "CDC investigates after 4 patients got sepsis from contaminated platelet transfusions," 13 June 2019 The Raptors hold a 3-1 series lead, and are one win away in a potentially decisive Game 5 in Toronto on Monday that would set various chain reactions. Mark Medina, The Mercury News, "Warriors explain what it will take to overcome 3-1 series deficit to Raptors," 8 June 2019 But the colt swung wide in the far turn at Churchill Downs, impeding the path of War of Will and setting off a chain reaction that caused Long Range Toddy and Bodexpress to drop from contenders to also-rans. Mark Inabinett |,, "Belmont Stakes 2019: No Triple Crown at stake, but Kentucky Derby still looms large," 7 June 2019 The skin’s response of UVB cause a chain reaction of other responses that begin with the release of chemicals, known as chemokines and cytokines. Tiffany Dodson, SELF, "9 Soothing Products People Swear By for Sunburn Relief," 25 May 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

14 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

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of or relating to the heavens

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