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 reductional (audio) , -​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

Specifically, that includes on-the-ground harm reduction measures, such as naloxone (which can reverse opioid overdoses) and fentanyl test strips, as well as basic education for people taking these drugs in both prescription and illicit contexts. Sarah Jacoby, SELF, "Fentanyl Now Officially Causes the Most Drug Overdose Deaths in the U.S.," 20 Dec. 2018 This should have resulted in a substantial reduction in light from the FEL but didn’t. Chris Lee, Ars Technica, "Single-beam laser becomes multi-beam laser by kicking electrons," 5 Dec. 2018 Environmentalists have been pushing electric cars as a kind of harm-reduction method for transportation for a very long time. Elizabeth Lopatto, The Verge, "Welcome to This Week in Elon," 31 Aug. 2018 But Rolando said one of the most important efforts in suicide reduction is storytelling. Elena Weissmann, Milwaukee Journal Sentinel, "Wisconsin suicide rate has increased 25 percent since '99, mirroring national problem," 14 June 2018 The superintendent has proposed $6.7 million in reductions throughout the budget. Allan Vought, The Aegis, "Harford school board faces critical decisons on budget, next superintendent," 8 June 2018 The next two biggest drivers of cost reductions for solar cells since 1980 have been changes in the price of silicon and non-silicon materials. Megan Geuss, Ars Technica, "How the falling cost of solar panels can teach us to make new tech affordable," 26 Nov. 2018 According to the company, patient data shows an average of 24-percent fat reduction after just one treatment. Macaela Mackenzie, Allure, "Exclusive: Cutera Is Launching TruSculpt iD, a 15-Minute Body-Contouring Treatment," 25 Sep. 2018 The International Energy Agency recently estimated that the gas industry could easily reduce its methane emissions by 75 percent — and that the bulk of those reductions would pay for themselves in the form of saved gas. Eric Levitz, Daily Intelligencer, "Natural Gas Is Hurting the Climate More Than We Thought," 22 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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Last Updated

16 Mar 2019

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Time Traveler for reduction

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

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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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