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

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.
Recent Examples on the Web The United States' goal for reducing the greenhouse gas emissions that cause climate change is a 50% to 52% reduction from 2005 levels by 2030. Elizabeth Weise, USA TODAY, 6 Aug. 2022 Since the 1980s, the Fed’s overall reduction of its benchmark interest rate from 18% to a range of 2.25%-2.50% has been a boon to bondholders since as rates go down, bond values go up. Derek Horstmeyer, WSJ, 5 Aug. 2022 Smaller firms that have little or no market power will probably not see any reduction in fees from this. Ike Brannon, Forbes, 3 Aug. 2022 Estimates showed a net increase of 244,000 new immigrants between 2020 and 2021 — roughly half the 477,000 new immigrant residents recorded between 2019 and 2020 and a drastic reduction from more than 1 million reported from 2015 to 2016. Summer Lin, Los Angeles Times, 29 July 2022 The millage amount and term were changed so the issue could be voted on again by the commissioners, with the millage rate now set at 0.95, a slight reduction from the 0.9615 originally envisioned. Eric D. Lawrence, Detroit Free Press, 15 July 2022 That’s a 20% volume reduction from the last generation. Jacob Siegal, BGR, 8 July 2022 The ministers also agreed to endorse the key parameters of a sweeping carbon market reform as proposed by the commission, including a 61% reduction of emissions in the cap-and-trade program by 2030 from 2005 levels. John Ainger, Fortune, 29 June 2022 Under the bill, the 25% reduction in plastic from single-use products would start in 2032. Kathleen Ronayne,, 18 June 2022 See More

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.

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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Dictionary Entries Near reduction

reductio ad absurdum


reduction crusher

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Statistics for reduction

Last Updated

9 Aug 2022

Cite this Entry

“Reduction.” Dictionary, Merriam-Webster, Accessed 18 Aug. 2022.

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More Definitions for reduction


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

More from Merriam-Webster on reduction

Nglish: Translation of reduction for Spanish Speakers

Britannica English: Translation of reduction for Arabic Speakers Encyclopedia article about reduction


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