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 Each time the Big Ten moved, the MAC was caught in the chain reaction. Evan Petzold, Detroit Free Press, "MAC commissioner shocked at timing of Big Ten's decision to drop non-conference foes," 10 July 2020 The fire started when a 6-inch mortar exploded inside its launching tube, sparking a chain reaction, fire officials said. Dana Branham, Dallas News, "Malfunction during Plano fireworks display sparks grass fire," 5 July 2020 On the PGA Tour, McDowell, Brooks Koepka and Webb Simpson were among five players who withdrew from the Travelers Championship, four of them out of a chain reaction of caution. Staff And News Services,, "NBA, MLB and PGA Tour players test positive for new coronavirus," 24 June 2020 This put pressure on these companies to change, seemingly sparking a chain reaction that, still, seemed cynical to some. Brent Schrotenboer, USA TODAY, "Does it really matter if Aunt Jemima and Uncle Ben get retired?," 23 June 2020 In Iowa, where summer baseball and softball leagues start games on June 15 with fans in attendance, a positive test will trigger a chain reaction from the school to Iowa’s department of public health, which can then start tracing and testing. Ethan Sears, The Indianapolis Star, "How states around the country are planning a return for high school sports," 11 June 2020 The researchers also note that 84 percent of species with relatively small populations (under 5,000) live near species that have exceptionally small populations (under 1,000), putting constraints on the ecosystem that can cause a chain reaction. Fox News, "Animals and plants are going extinct at an 'unprecedented rate,' shocking study says," 3 June 2020 The experiment offered a glimpse of the complex chain reaction that occurs when an exotic plant is introduced. Ula Chrobak, Popular Science, "Planting invasive species could make our carbon problem worse," 28 May 2020 The chain reactions happened around 12:30 p.m. on both sides of I-39 near County Highway D in Portage County. Meg Jones, Milwaukee Journal Sentinel, "'It was horrible': Dust blowing across Wisconsin interstate in Plainfield causes chain-reaction crashes involving 37 vehicles," 3 May 2020

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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Time Traveler for chain reaction

Time Traveler

The first known use of chain reaction was circa 1902

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Statistics for chain reaction

Last Updated

18 Jul 2020

Cite this Entry

“Chain reaction.” Dictionary, Merriam-Webster, Accessed 6 Aug. 2020.

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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

Thesaurus: All synonyms and antonyms for chain reaction Encyclopedia article about chain reaction

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