reduce

American  

[ri-doos, -dyoos] / rɪˈdus, -ˈdjus /

verb (used with object)

• reduces,
  present (3rd person singular)
• reduced,
  past participle,  past
• reducing
  present participle

1. 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

2. to lower in degree, intensity, etc..

   to reduce the speed of a car.

   Synonyms:

   abate, attenuate, lessen

3. to bring down to a lower rank, dignity, etc..

   a sergeant reduced to a corporal

   Synonyms:

   humble, demote, degrade

   Antonyms:

   exalt, elevate

4. to treat analytically, as a complex idea.

5. to lower in price.

6. to bring to a certain state, condition, arrangement, etc..

   to reduce glass to powder.

7. to bring under control or authority.

   Synonyms:

   overpower, overcome, vanquish, subject, conquer, subjugate, subdue

8. Cooking. to evaporate water from (a sauce, soup, or other liquid), usually by boiling.

9. Photography. to lessen the density of (an exposed negative).

10. to adjust or correct by making allowances, as an astronomical observation.

11. Mathematics. to change the denomination or form, but not the value, of (a fraction, polynomial, etc.).

12. 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.

13. Chemistry, Metallurgy. to bring into the metallic state by separating from nonmetallic constituents.

14. to thin or dilute.

    to reduce paint with oil or turpentine.

15. to lower the alcoholic concentration of (spirits) by diluting with water.

16. Surgery. to restore to the normal place, relation, or condition, as a fractured bone.

17. 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.

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verb (used without object)

• reduces,
  present (3rd person singular)
• reduced,
  past participle,  past
• reducing
  present participle

1. to become reduced.

2. to become lessened, especially in weight.

3. to be turned into or made to equal something.

   All our difficulties reduce to financial problems.

4. Cell Biology. to undergo meiosis.

reduce British  

/ rɪˈdjuːs /

verb

1. (also intr) to make or become smaller in size, number, extent, degree, intensity, etc

2. to bring into a certain state, condition, etc

   to reduce a forest to ashes

   to reduce someone to despair

3. (also intr) to make or become slimmer; lose or cause to lose excess weight

4. to impoverish (esp in the phrase in reduced circumstances )

5. to bring into a state of submission to one's authority; subjugate

   the whole country was reduced after three months

6. to bring down the price of (a commodity)

   the shirt was reduced in the sale

7. to lower the rank or status of; demote

   he was reduced from corporal to private

   reduced to the ranks

8. to set out systematically as an aid to understanding; simplify

   his theories have been reduced in a popular treatise

9. maths to modify or simplify the form of (an expression or equation), esp by substitution of one term by another

10. cookery to make (a sauce, stock, etc) more concentrated by boiling away some of the water in it

11. to thin out (paint) by adding oil, turpentine, etc; dilute

12. (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

13. 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

14. surgery to manipulate or reposition (a broken or displaced bone, organ, or part) back to its normal site

15. (also intr) biology to undergo or cause to undergo meiosis

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Other Word Forms

Derived Forms

• reducibility
  noun
• overreduce
  verb
• antireducing
  adjective
• nonreducing
  adjective
• reducible
  adjective
• reducibly
  adverb

Inflected Forms

Participles

• reducing
  present
• reduced
  past

Conjugated Forms

Present

• reduce
  simple
• reduces
  simple
• have reduced
  perfect
• has reduced
  perfect
• am reducing
  progressive
• are reducing
  progressive
• is reducing
  progressive
• have been reducing
  perfect progressive
• has been reducing
  perfect progressive

Past

• reduced
  simple
• had reduced
  perfect
• was reducing
  progressive
• were reducing
  progressive
• had been reducing
  perfect progressive

Future

• will reduce
  simple
• will have reduced
  perfect
• will be reducing
  progressive
• will have been reducing
  perfect progressive

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.

Example Sentences

See Examples For:

reduce reduces reduced reducing

Thomas Malthus promulgated the theory that population would grow at a faster rate than the means to support that population could, and so there would have to be ways to reduce population in unpleasant ways.

From The Wall Street Journal ● Aug. 16, 2026

Bring to a gentle simmer over medium heat, then reduce the heat as needed to maintain it.

From Salon ● Aug. 16, 2026

By influencing these receptors, the drugs can reduce food intake, promote weight loss, and help regulate blood sugar.

From Science Daily ● Aug. 15, 2026

When workers are more productive, companies can generate more profits and even reduce prices.

From MarketWatch ● Aug. 15, 2026

“Okay, you don’t need to go into deep sulking mode. I might reduce your time to five months, but it will depend on how you behave.”

From "Split the Sky" by Marie Arnold

This kind of exercise reduces the amount of weight and force placed on joints.

From Science Daily ● Aug. 16, 2026

He reduces Bourdain to a zygote who simply needed enough nurturing to become his older, cooler self, when he could, instead, read between the lines to find what makes young Tony special.

From Salon ● Aug. 12, 2026

"It helps them to be able to focus more on the activity that they're doing because it sort of reduces the fidgeting," she added.

From BBC ● Aug. 11, 2026

In a series of experiments at Duke University, scientists found that the act of measuring an activity reliably reduces enjoyment, making it feel like work.

From Slate ● Aug. 11, 2026

Every step up the chain reduces the amount of food energy by a factor of ten.

From "The Omnivore's Dilemma" by Michael Pollan

Another systematic review found exercises which challenged participants’ balance reduced fall rates by roughly 23%.

From Science Daily ● Aug. 16, 2026

This reduces the potential for tactical bad challenges to get a team reduced to 10 men.

From BBC ● Aug. 14, 2026

The Alpines see growing evidence for their argument that reduced costs will drive more consumption.

From The Wall Street Journal ● Aug. 13, 2026

The region’s Bay Area Rapid Transit commuter rail system reduced train speeds after the quake to complete safety inspections, and told riders to expect delays of about 20 minutes.

From Los Angeles Times ● Aug. 13, 2026

In a matter of minutes, the vast glittering school had been reduced to a few survivors, who quickly flitted away.

From "The Wild Robot Protects" by Peter Brown

At a low dose, the drug primarily works by reducing several harmful compensatory responses that occur when the heart is struggling.

From Science Daily ● Aug. 16, 2026

In his third term, Lula has been credited with expanding social programs, a major overhaul of the tax system, and reducing deforestation in the Amazon.

From Barron's ● Aug. 16, 2026

She said she saw architecture as a way of reducing the distance between people.

From The Wall Street Journal ● Aug. 15, 2026

I understand the usual arguments — reducing future RMDs, avoiding higher future tax brackets, and creating tax-free assets for heirs — but I’m not sure they carry much weight in my particular case.

From MarketWatch ● Aug. 15, 2026

Resistant houseflies may have the stable-fly habit of sitting still in one place, thus greatly reducing the frequency of their contact with residues of poison.

From "Silent Spring" by Rachel Carson

Related Words

• curtail
• cut
• cut down
• diminish
• dwindle
• knock off
• lessen
• lower
• pare
• scale down
• shorten
• slash
• trim
• weaken