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

Relevance
See All Synonyms & Antonyms in Thesaurus

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.
In an internal memo, Qualcomm Chief Executive Officer Cristiano Amon stated the reductions aim to foster a stronger performance culture and address ongoing shortfalls relative to operational expectations. — CNBC, 23 Oct. 2026 Its buttons include functions for turn signals, boost, and the drag reduction system, reducing the need to navigate touchscreen menus during demanding driving. — Aamir Khollam, Interesting Engineering, 23 Oct. 2026 Those initiatives included bold greenhouse gas reduction targets and the nation-leading cap-and-invest program, which forces large polluters to pay for their share of planet-warming emissions. — Los Angeles Times, 23 Oct. 2026 In a clinical study of 194 patients, 80% of them reported significant reductions in knee pain that lasted for at least a full year after receiving the treatment. — Khloe Quill, FOXNews.com, 23 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

See All Rhymes for reduction

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 27 Oct. 2026.

Copy Citation

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

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Last Updated: - Updated example sentences

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of milieu

See Definitions and Examples »

Popular in Grammar & Usage

See More

How to Use 'Who' vs. 'Whom'

Merriam-Webster’s Great Big List of Words You Love to Hate

'Affect' vs. 'Effect'

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Why is '-ed' sometimes pronounced at the end of a word?
See More

Popular in Wordplay

See More

The Longest Long Words List

9 Words That Sound Like Insults But Aren't

12 Lovely and Unusual Words for the Natural World

Why do we 'bury the lede?'

'Za' and 9 Other Words to Help You Win at SCRABBLE
See More

Popular

See More

How to Use 'Who' vs. 'Whom'

The Longest Long Words List

9 Words That Sound Like Insults But Aren't
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
different halloween monsters in silhouette
A Monstrous Vocab Quiz Words That Go Bump in the Night
See All