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

Researchers expect states will be under pressure to reduce or eliminate programs like these to make up for nearly $900 billion in coming Medicaid reductions, since the federal government does not require states to cover respiratory care for people on ventilators or nursing home alternatives. —Jordan Rau, NPR, 29 Nov. 2025

Speed reduction, increased following distances, and clearing all vehicle windows of snow and ice have been repeatedly emphasized. —Hollie Silverman, MSNBC Newsweek, 29 Nov. 2025

Changes included a vastly superior viewfinder, AI autofocus (including noise reduction features) and more. —Chris McMullen, Space.com, 29 Nov. 2025

The results also showed CO2 reductions of 15 and 23 percent when five and 10 percent of the sand was replaced with biochar, respectively. —Georgina Jedikovska, Interesting Engineering, 28 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