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 \ 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 crowd cheer and Hinds respond by wreaking havoc, jumping off the drum riser, creating a chain reaction for the fans to dance wilder. Eve Barlow, GQ, "15 Hours With Hinds, Spain's Wildest Rock Band," 25 June 2018 That's based on the maximum amount of uranium or plutonium that can be put together without starting a chain reaction while the weapon is in storage. Andrew Karam, Popular Mechanics, "Nuclear Forensics: How Scientists Can Tell Whether North Korea Is Lying About Its Bomb Test," 7 Jan. 2016 Sacramento's sundry restrictions on recyclables are the result of a chain reaction stretching from China to Northern California, as The Sacramento Bee reported in March. Jordan Cutler-tietjen, sacbee, "Do you take recycling seriously? Here's how Sacramento's waste rules are changing," 10 July 2018 But not all uranium atoms can easily split apart and trigger a chain reaction. Umair Irfan, Vox, "Uranium enrichment will be a key point in talks with North Korea. Here’s what it is.," 11 June 2018 These refer to experiments involving a subcritical mass of nuclear materials that allow scientists to examine the performance and safety of weapons without triggering a nuclear chain reaction and explosion. Kim Tong-hyung, The Seattle Times, "Trump welcomes N. Korea plan to blow up nuke-site tunnels," 13 May 2018 By dropping the dome, Slotin had stopped any neutrons from escaping, giving the demon core enough energy to undergo a dangerous chain reaction. Julian G. West, The Atlantic, "The Atomic-Bomb Core That Escaped World War II," 2 Apr. 2018 This, in turn, almost always sets off a regurgitation chain reaction with her 5-year-old brother, who sees his sister’s expulsion and begins to dramatically expel himself. Jason Gay, WSJ, "Memo to Rolls-Royce: Family Car Rides Are Anything but Luxurious," 18 May 2018 The mutation spawns a chain reaction of identity crises. Helena Oliviero, ajc, "Things to do in and around Atlanta on Tuesday, May 15," 14 May 2018

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

6 Nov 2018

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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

: 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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