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

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 The debris from the crash then initiates a cascading chain reaction of billions of particles, known as an air shower, that blazes toward the ground and emits characteristic ultraviolet light. Adam Hadhazy, Discover Magazine, "Scientists Hunt for A Seeming Paradox: A Magnet With Only One Pole," 13 Nov. 2018 That new photon may strike another energized atom in turn, prompting the release of another photon, and so on, until all the atoms suddenly discharge in a rapid chain reaction. Jennifer Ouellette, Ars Technica, "2018 physics Nobel Prize honors 3, including first woman in 55 years," 2 Oct. 2018 Unable to absorb the massive energy, that floor would fail, transmitting the forces to the floor below, allowing the collapse to progress downward through the building in a chain reaction. Popular Mechanics Editors, Popular Mechanics, "Debunking the 9/11 Myths: Special Report - The World Trade Center," 10 Sep. 2018 Ostojic warned, echoing fears of a chain reaction throughout Balkans. Sylejman Kllokoqi, Fox News, "Serbia-Kosovo 'land swap' on the agenda in Brussels," 7 Sep. 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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Last Updated

16 Jan 2019

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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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