reduction

noun

re·​duc·​tion ri-ˈdək-shən How to pronounce reduction (audio)
plural reductions
Synonyms of reductionnext
1
: the act or process of reducing : the state of being reduced
2
a
: something made by reducing
b
: the amount by which something is reduced
3
[Spanish reducción, from Latin reduction-, reductio] : a South American Indigenous settlement directed by Jesuit missionaries
4
: meiosis sense 2
specifically : production of the gametic chromosome number in the first meiotic division
reductional
ri-ˈdək-sh(ə-)nəl How to pronounce reduction (audio)
adjective

Synonyms of 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The company says its indigo process uses soluble precursors that oxidize into insoluble pigment within the textile, avoiding the chemical reduction step used in conventional indigo dyeing. — Alexandra Harrell, Footwear News, 30 Oct. 2026 Google’s research suggests that SpaceX’s fully reusable Starship rocket could require approximately 1,800 flights to achieve significant cost reductions. — Aamir Khollam, Interesting Engineering, 30 Oct. 2026 The Department of Veterans Affairs cut average disability claims processing time from 141 days to 81, a 42% reduction, and pushed its backlog below 100,000 for the first time since 2020. — Billy Biggs, Forbes.com, 30 Oct. 2026 The reduction also means deputies assigned to Live Oak will no longer routinely respond to 55 types of calls across three priority levels. — Michael McGough, Sacbee.com, 30 Oct. 2026 See All Example Sentences for reduction

Word History

Etymology

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

First Known Use

15th century, in the meaning defined at sense 1

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

Phrases Containing reduction

Rhymes for reduction

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Browse Nearby Words

reductio ad absurdum
reduction
reductional
See all Nearby Words

Cite this Entry

“Reduction.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reduction. Accessed 1 Nov. 2026.

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Kids Definition

reduction

noun
re·​duc·​tion ri-ˈdək-shən How to pronounce reduction (audio)
1
: the act or process of reducing : the state of being reduced
2
a
: something made by reducing
b
: the amount by which something is reduced in price
3
: meiosis
especially : halving of the chromosome number in the reduction division
reductive
-ˈdək-tiv
adjective

Medical Definition

reduction

noun
re·​duc·​tion ri-ˈdək-shən How to pronounce reduction (audio)
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

Britannica.com: Encyclopedia article about reduction

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