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

The program has a total estimated cost of $5 billion, reflecting a slight reduction from earlier estimates. Washington Post, "Trump’s July 4 celebration will showcase some of the Pentagon’s deepest money pits, critics say," 3 July 2019 Gallagher’s attorney, Timothy Parlatore, said after Wednesday’s hearing that his team will ask the convening authority, Rear Admiral Bette Bolivar, to have Gallagher’s rank reduction suspended so that Gallagher could retire as a chief. San Diego Union-Tribune, "Navy SEAL Chief told jury deciding his sentence, “I’ve made mistakes”," 3 July 2019 Like Dallas County, Tarrant County would not make any reductions to its number of polling places until after the 2020 election cycle, if at all, Whitley said. Dallas News, "Amid worries over cutting polling places, Dallas County moves ahead with plan for voting centers by November," 2 July 2019 Other expense reductions have included consolidating bus routes, reducing utility costs through energy-efficiency projects, canceling summer school, refinancing long-term debt and delaying spending on maintenance. Bob Dohr, Milwaukee Journal Sentinel, "The Palmyra-Eagle School Board has taken the next step toward dissolving the school district," 2 July 2019 View the van's schedule at Valerie Royzman,, "New step to protect against ODs: Hamilton County offers fentanyl test strips," 2 July 2019 Vibrant orange sweet potato gnocchi, with a playfully non-traditional chew, sit in a thick, almost sticky chicken reduction cut with just a touch of acid. Dominic Armato, azcentral, "The best restaurants in Scottsdale and Paradise Valley," 1 July 2019 So far the specific contribution of the cap-and-trade scheme to emissions reductions is hard to measure, says Dallas Burtraw of Resources for the Future, who chairs the programme’s market advisory committee. The Economist, "Can American states slow global warming on their own?," 29 June 2019 The bad news is that $1.7 million in other revenue reductions would cut the net increase to almost $5.8 million. Jerry Fallstrom,, "Delay in $7.8M FEMA reimbursement throws hitch into Lake County budget planning," 28 June 2019

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

6 Jul 2019

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 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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Comments on reduction

What made you want to look up reduction? Please tell us where you read or heard it (including the quote, if possible).


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