reduction

noun

re·​duc·​tion ri-ˈdək-shən 

plural reductions

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 

adjective

Synonyms of reduction

• deduction
• discount

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

Spaceflight caused a 20% reduction in chlorophyll a, the main pigment involved in photosynthesis, but the spores seemed to be healthy despite that drop, the team found. —Mike Wall, Space.com, 22 Nov. 2025

This is due to typical power plant maintainence and forced plant outages as well as reductions in power capacity due to winter conditions. —Spencer Kimball,gabriel Cortés, CNBC, 22 Nov. 2025

Gjeltema turned to a program enacted under a California state law, the Mills Act that could give her home a reduction in property tax in exchange for a contractual commitment to do work to preserve the property. —Graham Womack, Sacbee.com, 22 Nov. 2025

There has been a rise in Ohio traffic deaths from 2018 to a peak of 1,356 in 2021, but Ohio has seen a reduction in traffic deaths over the last three years, according to the Ohio Department of Transportation. —Kaycee Sloan, Cincinnati Enquirer, 21 Nov. 2025

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

Phrases Containing reduction

• oxidation-reduction
• reduction division
• reduction gear

Rhymes for reduction

• abduction
• adduction
• conduction
• construction
• deduction
• destruction
• eduction
• induction
• instruction
• obstruction
• production
• seduction

Kids Definition

reduction

noun

re·​duc·​tion ri-ˈdək-shən 

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 

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