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

Sharper quantum benchmark Martin Roetteler, IonQ’s vice president of quantum applications R&D, said the reduction in resources came from progress across the stack. — Aamir Khollam, Interesting Engineering, 8 Sep. 2026

Last year, voters living around Aspen approved sales and property tax increases to specifically fund wildfire reduction. — Jeff Todd, CBS News, 8 Sep. 2026

These moments of hormonal upheaval are linked to a rewiring of neural networks and reductions in the volume of the brain’s outer, wrinkly layer—called cortical gray matter—which plays a role in memory, reasoning and movement. — Claire Cameron, Scientific American, 8 Sep. 2026

The conversation often focuses on autonomous factories, robotics and workforce reduction. — Luis Garelli, Forbes.com, 8 Sep. 2026

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