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

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

Evidence of this is the terms by which Ronaldo was allowed to leave the club: a 90 percent reduction of his release clause, from 1 billion to 100 million euros for a five-time Ballon d'Or winner and the all-time leading goal scorer in club history. Juan Pimiento,, "Ronaldo's shock transfer, the World Cup semis and the best of the week in soccer," 12 July 2018 Their options are: Finish their studies at another Art Institute campus (the closest are in Virginia Beach, Va., and Pittsburgh) with a 50 percent reduction in tuition. Annabelle Williams,, "Art Institute of Philadelphia closing leaves students and employees with hard decisions," 12 July 2018 As building accelerates — more than 5 million square feet of office and retail space and thousands of housing units are planned — the Downtown Columbia Transportation Demand Management Plan presents ways to achieve a 15 percent reduction. Kate Magill, Howard County Times, "Howard County wants plans for limiting Columbia traffic as development continues," 12 July 2018 At the median, convulsive seizures dropped by 63 percent in the Dravet patients given ZX008 compared with a 1 percent reduction in placebo patients. Adam Feuerstein, STAT, "Zogenix to submit anti-seizure drug for approval after clinical trial confirms benefit," 12 July 2018 Transferring to another Dream Center campus will make students eligible for a 50 percent tuition reduction, while those transferring to a partner institution will be eligible for a $5,000 grant. Rebecca Aydin,, "Two Bay Area colleges to close, lay off hundreds of staff," 11 July 2018 The participants also exhibited a 35 percent reduction in their usual physiological resting rates. Southern Living, "This Song Will Instantly Lower Your Stress Level By 65 Percent," 3 July 2018 However, this 85 percent reduction in storage comes at the cost of several key features. Lilly Milman, Billboard, "Spotify Is Workshopping a Space-Saving Lite Version," 2 July 2018 For a $400,000 home in 2018, the tax will be $320.80, which represents an 11.64 percent reduction in taxes year to year if the home is valued at the same amount in both years. Karen Huppertz, ajc, "Berkeley Lake plans to lower millage rate," 30 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

12 Oct 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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