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

But banning buybacks banishes all wonderful chain reactions. Ken Fisher, USA TODAY, "Despite what politicians say, stock buybacks aren't evil," 22 Apr. 2018 In 1969, a group of Native students stormed the island by boat, launching a 19-month occupation that sparked a chain reaction of Indigenous activism throughout the country. Delilah Friedler, Teen Vogue, "Activist LaNada War Jack of the Bannock Nation Details Her Time Occupying Alcatraz," 21 Mar. 2019 After that, no further decision is expected for 3½ months, when Europe holds parliamentary elections that could kick off a chain reaction of appointments to other top European posts, including head of the European Commission, the EU’s executive arm. Tom Fairless, WSJ, "Europe’s Biggest Job Opening in Years: President of the ECB," 11 Feb. 2019 That killing allegedly sparked a chain reaction that led other members of Mr. Slatten’s convoy to unleash a barrage of gunfire. Aruna Viswanatha, WSJ, "Ex-Blackwater Guard Goes to Trial for Third Time in Less Than Five Years," 5 Nov. 2018 Reactica 2018 Domino Building and Topple Event Alex Huang and company are back to build the biggest chain reaction in California. Chronicle Staff Report, San Francisco Chronicle, "Kids listings," 14 June 2018 This chain reaction could divert workers and money at a time when new employees are seen as crucial to ensure ample funding for the wave of retiring baby boomers – putting payouts for millions of pensioners at risk. Damian Paletta, Anchorage Daily News, "In land of Peeps, a fight threatens U.S. pension plans," 30 Mar. 2018 By contrast, the at the time controversial decision to block T-Mobile and Sprint from merging unleashed a chain reaction of events that’s brought affordable unlimited data plans to millions of Americans. Matthew Yglesias, Vox, "Why criticism of Amazon isn’t sticking," 11 Dec. 2018 In what appeared to be a chain reaction, two more cars parked in front of the house - a van and a Ford F-150 pickup - were also damaged. Alyson Ward, Houston Chronicle, "Driver crashes into northeast Houston yard," 21 Jan. 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

22 May 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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