Synonyms

reduce

American

[ri-doos, -dyoos] / rɪˈdus, -ˈdjus /

verb (used with object)

to bring down to a smaller extent, size, amount, number, etc..

to reduce one's weight by 10 pounds.

Synonyms:

abate, attenuate, lessen, retrench, contract, curtail, abridge, shorten, decrease, diminish

Antonyms:

increase
to lower in degree, intensity, etc..

to reduce the speed of a car.

Synonyms:

abate, attenuate, lessen
to bring down to a lower rank, dignity, etc..

a sergeant reduced to a corporal

Synonyms:

humble, demote, degrade

Antonyms:

exalt, elevate
to treat analytically, as a complex idea.
to lower in price.
to bring to a certain state, condition, arrangement, etc..

to reduce glass to powder.
to bring under control or authority.

Synonyms:

overpower, overcome, vanquish, subject, conquer, subjugate, subdue
Cooking. to evaporate water from (a sauce, soup, or other liquid), usually by boiling.
Photography. to lessen the density of (an exposed negative).
to adjust or correct by making allowances, as an astronomical observation.
Mathematics. to change the denomination or form, but not the value, of (a fraction, polynomial, etc.).
Chemistry.
1. to add electrons to.
2. to deoxidize.
3. to add hydrogen to.
4. to change (a compound) so that the valence of the positive element is lower.
Chemistry, Metallurgy. to bring into the metallic state by separating from nonmetallic constituents.
to thin or dilute.

to reduce paint with oil or turpentine.
to lower the alcoholic concentration of (spirits) by diluting with water.
Surgery. to restore to the normal place, relation, or condition, as a fractured bone.
Phonetics. to modify the quality of (a speech sound) to one of lesser distinctiveness, especially to pronounce (an unstressed vowel) as (ə) or another centralized vowel, as in the unstressed syllables of medicinal.

verb (used without object)

to become reduced.
to become lessened, especially in weight.
to be turned into or made to equal something.

All our difficulties reduce to financial problems.
Cell Biology. to undergo meiosis.

reduce British

/ rɪˈdjuːs /

verb

(also intr) to make or become smaller in size, number, extent, degree, intensity, etc
to bring into a certain state, condition, etc

to reduce a forest to ashes
to reduce someone to despair
(also intr) to make or become slimmer; lose or cause to lose excess weight
to impoverish (esp in the phrase in reduced circumstances )
to bring into a state of submission to one's authority; subjugate

the whole country was reduced after three months
to bring down the price of (a commodity)

the shirt was reduced in the sale
to lower the rank or status of; demote

he was reduced from corporal to private
reduced to the ranks
to set out systematically as an aid to understanding; simplify

his theories have been reduced in a popular treatise
maths to modify or simplify the form of (an expression or equation), esp by substitution of one term by another
cookery to make (a sauce, stock, etc) more concentrated by boiling away some of the water in it
to thin out (paint) by adding oil, turpentine, etc; dilute
(also intr) chem
1. to undergo or cause to undergo a chemical reaction with hydrogen or formation of a hydride
2. to lose or cause to lose oxygen atoms
3. to undergo or cause to undergo an increase in the number of electrons Compare oxidize
photog to lessen the density of (a negative or print) by converting some of the blackened silver in the emulsion to soluble silver compounds by an oxidation process using a photographic reducer
surgery to manipulate or reposition (a broken or displaced bone, organ, or part) back to its normal site
(also intr) biology to undergo or cause to undergo meiosis

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Derived Forms

Inflected Forms

Participles

Conjugated Forms

Present

Past

Future

Etymology

Origin of reduce

First recorded in 1325–75; Middle English reducen “to lead back,” from Latin redūcere “to lead back, bring back,” equivalent to re- re- + dūcere “to lead”

Explanation

You reduce something when you lessen its volume, size, or degree. That's why we say when someone goes on a diet, it's because they want to reduce; it's a polite way of suggesting they need to drop pounds and become a smaller size. The word reduce first appeared in Old French during the 14th Century, when it meant "bring back." From the Latin re, which meant "back," coupled with ducere, meaning "bring or lead" — we ended up with reduce. The current meaning, "to lessen," appeared in the late 1700's, drawn from the word's military use, "reduce to ranks," which meant break into smaller units. Cooks use the word reduce when they reduce a liquid, boiling it down until it has less volume and is thicker.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

reduce reduces reduced reducing

The grass, native plants and trees are intended to provide shade and reduce heat on a schoolyard that was previously made up largely of asphalt.

From Los Angeles Times ● Sep. 13, 2026

Its drug ziltivekimab was designed to block IL-6 and reduce inflammation linked to heart disease.

From The Wall Street Journal ● Sep. 12, 2026

This destruction and the blockage of seaports are likely to reduce national GDP by 1.5 points, he added, with some Western experts calling the situation "catastrophic."

From Barron's ● Sep. 12, 2026

Accurately identifying a person's risk can help doctors determine who is most likely to benefit from preventive treatments, including statins, which lower cholesterol and reduce cardiovascular risk.

From Science Daily ● Sep. 12, 2026

I showed him how to set up his graphs, how to utilize the tables in his textbook, and how to reduce experimental findings to mathematical formulas.

From "The Chosen" by Chaim Potok

Jefferies cuts its estimated probability of success to 5% from 25% and reduces peak sales assumptions for the drug candidate by 50%.

From The Wall Street Journal ● Sep. 9, 2026

Analysts believe this shift reduces the risk of a gas price spike translating into electricity bill hikes as severe as those seen in 2022, although costs are still expected to rise.

From Barron's ● Sep. 8, 2026

This process reduces genetic diversity within the successful population.

From Science Daily ● Sep. 7, 2026

"If soccer is strengthened in the developing world, global competition increases, which ultimately reduces Uefa's market power and provides more competition for its flagship tournaments," Fifa said.

From BBC ● Sep. 3, 2026

“Yes, I prefer being straightforward and prefer others to be straightforward with me. It reduces the space between people. Saves time.”

From "The Bletchley Riddle" by Ruta Sepetys and Steve Sheinkin

The war in the Middle East has reduced traffic and fees from carriers using their airspace to get to and from the Persian Gulf.

From The Wall Street Journal ● Sep. 13, 2026

Blocking sEH increased epoxy-oxylipin levels, helped pain resolve more quickly, and sharply reduced the number of intermediate monocytes found in both the blood and tissue.

From Science Daily ● Sep. 13, 2026

Soybeans were climbing on a fresh, large U.S. sale to China that reduced supply.

From MarketWatch ● Sep. 13, 2026

The case has seen the once high-flying Cerimedo reduced to a slumping presence in a hoodie as authorities have shuffled the baldish, heavyset figure to hearings and lockups.

From Los Angeles Times ● Sep. 13, 2026

One of his first tasks was to convince the generic manufacturers that reduced second-line antibiotic prices could still result in significant revenues and profits.

From "Mountains Beyond Mountains" by Tracy Kidder and Michael French

One of the biggest challenges to reducing ectopic pregnancy deaths nationwide is the lack of awareness, research and data.

From Salon ● Sep. 13, 2026

The reality is by having a higher age rating than Spider-Man, it is by definition reducing the amount of people who can buy the game.

From BBC ● Sep. 12, 2026

By suppressing PCSK9, the treatment helps cells remove more cholesterol from the bloodstream, potentially reducing the buildup of fatty plaques inside arteries that can lead to atherosclerosis.

From Science Daily ● Sep. 10, 2026

All the evidence I can find suggests that EVs are reducing China’s emissions, on balance.

From The Wall Street Journal ● Sep. 10, 2026

She spoke with a quiet fury, her anger reducing to a hard crust you’d need a hammer to chip away.

From "We Are the Ants" by Shaun David Hutchinson

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023