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

One of her proposals called for an immediate £500,000 limit which would reduce to £100,000 in the second calendar year.

From BBC ● Sep. 3, 2026

The deer also reduce habitat and food sources for native birds and mammals, like the endemic Catalina Island fox, he said.

From Los Angeles Times ● Sep. 2, 2026

That “certainly will reduce affordability, particularly for the potential first-time home buyer,” he said.

From The Wall Street Journal ● Sep. 2, 2026

Moroccan police made "no serious attempt to try to reduce, disperse or move the mass of people away from the border perimeter", the report said.

From Barron's ● Sep. 2, 2026

Many people had put off their visits in the expectation that the nation’s worsening economic crisis and pressure from Congress eventually would compel the railroads to reduce their Chicago fares.

From "The Devil in the White City" by Erik Larson

“Every October, USC reduces our health care options, and at this point only the most expensive plan covers my doctors,” said Sanjay Madhav, a Viterbi School of Engineering professor of practice who has muscular dystrophy.

From Los Angeles Times ● Sep. 3, 2026

Government reduces all of them to a percentage.

From MarketWatch ● Aug. 31, 2026

The use of the dollar in international settlements reduces exchange-rate risks and transaction costs, keeps demand for dollars high, and maintains its buying power for families working to achieve their American Dream.

From The Wall Street Journal ● Aug. 30, 2026

Signing from within the league also reduces some of the uncertainty, with recruitment teams already familiar with a player's qualities and performances.

From BBC ● Aug. 30, 2026

Some malaria mosquitoes have a habit that so reduces their exposure to DDT as to make them virtually immune.

From "Silent Spring" by Rachel Carson

On Thursday, the number of vessels passing through the Panama Canal will be reduced by more than 10% in anticipation of lower rainfall.

From BBC ● Sep. 3, 2026

It has reduced roles focused primarily on coordination and cut the number of teams of just one to two employees by 50%.

From Los Angeles Times ● Sep. 2, 2026

The Middle East conflict influenced spending behavior, with falls in fuel consumption seen in response to elevated prices, and reduced domestic and international travel, the data showed.

From The Wall Street Journal ● Sep. 2, 2026

The first law allowing an early claiming age was passed in 1956 and let women workers and wives of workers claim retirement benefits at a reduced rate beginning at age 62.

From MarketWatch ● Sep. 2, 2026

The theater had lost its luster and its high-society audience, reduced to booking vaudeville comedians, clog dancers, and trick dogs.

From "American Spirits" by Barb Rosenstock

The Vaccine Integrity Project, for example, concluded that the newest versions of the COVID, RSV and flu vaccines work at reducing severe illness, hospitalization and death, they concluded in the journal JAMA.

From Salon ● Sep. 2, 2026

"Additionally, our study suggests potential therapeutic opportunities to expedite this process, such as repurposing drugs like SGLT2 inhibitors, which have shown promise in reducing inflammation and promoting immune-mediated clearance of senescent cells in obesity."

From Science Daily ● Sep. 2, 2026

In Scotland, more than 8,500 prisoners are being held in a system designed for 7,805, placing prison staff and inmates under pressure and reducing time that can be spent on rehabilitation.

From BBC ● Sep. 1, 2026

Pate said the government would send a bill to the National Assembly to push forward with the decriminalisation plan, with the aim of reducing suicide deaths and attempts by 15 percent by 2030.

From Barron's ● Sep. 1, 2026

She explains hard things like reducing fractions and turning them into decimals.

From "Towers Falling" by Jewell Parker Rhodes

Related Words

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