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

Be consistent since a sudden reduction in soil moisture can diminish the size of each fruit. —Joshua Siskin, Oc Register, 28 May 2026

The researchers noted a dose response in both the amount of PCSK9 the treatment knocked out and the size of the LDL reduction; the larger the dose, the less PCSK9, and the lower the LDL. —Beth Mole, ArsTechnica, 28 May 2026

Participants reported reductions in cramping, headaches, fatigue, bloating, and food cravings across multiple menstrual cycles. —Tanya Benedicto Klich, Forbes.com, 28 May 2026

If a serious spending-reduction effort were somehow mounted anyway, the result would likely be positive for bonds — but ambiguous for equities, since the economic drag could easily outweigh the benefit of lower interest rates. —Nick Lichtenberg, Fortune, 28 May 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