re·​duc·​tion | \ri-ˈdək-shən \

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, -​shə-​nᵊl \ adjective

Synonyms & Antonyms for reduction


abatement, deduction, discount


accession, addition

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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

But a few specs are being cut back to account for the $10 price reduction. Jacob Kastrenakes, The Verge, "Raspberry Pi made a cheaper version of its most powerful PC," 15 Nov. 2018 That might have empowered them to stand up to their partners, which could have contributed to a reduction in violence. Dylan Matthews, Vox, "How a $50-a-year nutrition program cut domestic violence in Bangladesh," 12 Nov. 2018 Up to a 24 percent fat reduction can be seen six to 12 weeks after treatment. Allure, "The Skin-Care Glossary: A Comprehensive Guide to Everything You Need to Know," 17 Aug. 2018 Attorneys negotiated the $21 million price reduction after disputes threatened to torpedo the deal. Washington Post, "Judge approves revised Weinstein Co. bankruptcy sale plan," 11 July 2018 In the climate category, the Finnish city of Li won thanks to a 50 % reduction in emissions from 2007 to 2015. Valerie Sweeten, Houston Chronicle, "Education, training crucial to energy industry success," 8 July 2018 Economists typically argue that rent control will lead to a reduction in the quality and quantity of housing available. Phillip Molnar,, "Could rent control be coming to San Diego?," 3 July 2018 From July 3-14, Trish Lee Bridal will hold a liquidation sale at the showroom in Union Square with price reductions up to 80 percent. Tony Bravo,, "Trish Lee Bridal sells company to SF startup Anomalie," 2 July 2018 In its regulatory impact analysis, the agency said the rule would lead to reductions in particulate matter that could prevent between 4,200 and 11,000 premature deaths. Maxine Joselow, Science | AAAS, "Clean air advocates worried by EPA’s move to rethink cost-benefit calculations," 25 June 2018

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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Statistics for reduction

Last Updated

7 Dec 2018

Look-up Popularity

Time Traveler for reduction

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

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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 \

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 \

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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