re·​duc·​tion | \ ri-ˈdək-shən How to pronounce reduction (audio) \

Definition of reduction

1 : the act or process of reducing : the state of being reduced
2a : something made by reducing
b : the amount by which something is reduced
3 [Spanish reducción, from Latin reduction-, reductio] : a South American Indian settlement directed by Jesuit missionaries
4 : meiosis sense 2 specifically : production of the gametic chromosome number in the first meiotic division

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Other Words from reduction

reductional \ ri-​ˈdək-​shnəl How to pronounce reduction (audio) , -​shə-​nᵊl \ adjective

Synonyms & Antonyms for reduction



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Examples of reduction in a Sentence

a drastic reduction in size Many voters want to see some reduction of the deficit. There is a 20 percent reduction on selected items during this sale.
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Recent Examples on the Web The city practices harm reduction, investing in reducing overdose risks and increasing housing, mental health and drug treatment. Mallory Moench, San Francisco Chronicle, "Many San Franciscans in jail struggle with addiction. Would this polarizing treatment option help them?," 12 May 2021 Hollywood dramas: say, people who make their progress slowly, who falter, who benefit from harm reduction, who learn that recovery is about more than their own will to endure suffering, whose addiction isn’t even their biggest problem in life. New York Times, "Hollywood Has a New Way to Dramatize Addiction," 11 May 2021 Some lawmakers, as well as nicotine industry supporters and harm reduction advocates, consider the recent federal approach prohibitionist and draconian. Jamie Ducharme, Time, "How the FDA's Menthol Cigarette Ban Fits Into a New Era of U.S. Tobacco Regulation," 29 Apr. 2021 That’s a quandary, though, because arguably the societal benefits are bigger than the individual ones—putting do-no-harm into conflict with harm reduction. Adam Rogers, Wired, "A Vaccine Can Be Bad for a Person but Awesome for All People," 23 Apr. 2021 It’s a containment and harm-reduction strategy, Casanova said. Steve Lopez Columnist, Los Angeles Times, "Column: He went from Yale to Wall Street to homelessness. Now he’s rising back up," 17 Apr. 2021 The prevention team is committed to the citizens of Carroll County in providing resources and information about prevention, early Intervention, recognizing signs and symptoms, understanding risk factors, and harm reduction. Melanie Watson,, "Health Department: April is National Alcohol Awareness Month," 17 Apr. 2021 Harm reduction is a strategy that helps people who use drugs stay healthy and alive. Alia E. Dastagir, USA TODAY, "Demi Lovato has alcohol, weed in moderation: What experts think of the 'California Sober' approach," 6 Apr. 2021 One solution to stop HIV from spreading was by providing clean needles — a harm reduction approach. Robert Klitzman, STAT, "How will people act after getting vaccinated? The complex psychology of safety," 30 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'reduction.' 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 reduction

15th century, in the meaning defined at sense 1

History and Etymology for reduction

Middle English reduccion restoration, from Middle French reducion, from Late Latin & Latin; Late Latin reduction-, reductio reduction (in a syllogism), from Latin, restoration, from reducere

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Time Traveler for reduction

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The first known use of reduction was in the 15th century

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Statistics for reduction

Last Updated

17 May 2021

Cite this Entry

“Reduction.” Dictionary, Merriam-Webster, Accessed 18 May. 2021.

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More Definitions for reduction



English Language Learners Definition of reduction

: the act of making something smaller in size, amount, number, etc. : the act of reducing something
: an amount by which something is reduced


re·​duc·​tion | \ ri-ˈdək-shən How to pronounce reduction (audio) \

Kids Definition of reduction

1 : the act of making something smaller or less : the state of being made smaller or less a reduction in noise
2 : the amount by which something is made smaller or less


re·​duc·​tion | \ ri-ˈdək-shən How to pronounce reduction (audio) \

Medical Definition of reduction

1 : the replacement or realignment of a body part in normal position or restoration of a bodily condition to normal
2 : the process of reducing by chemical or electrochemical means
3 : the psychological diminishment of emotion or needs through activity or adjustment
4 : meiosis specifically : production of the gametic chromosome number in the first meiotic division

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