reducer

American  

[ri-doo-ser, -dyoo-] / rɪˈdu sər, -ˈdju- /

noun

reducers plural

1. a person or thing that reduces.

2. Photography.

   1. an oxidizing solution for lessening the density of an exposed negative.

   2. a developing agent.

3. (in plumbing) a coupling decreasing in diameter at one end.

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reducer British  

/ rɪˈdjuːsə /

noun

1. photog a chemical solution used to lessen the density of a negative or print by oxidizing some of the blackened silver to soluble silver compounds Compare intensifier

2. a pipe fitting connecting two pipes of different diameters

3. a person or thing that reduces

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Other Word Forms

Derived Forms

• antireducer
  noun

Inflected Forms

Nouns

• reducers
  plural

Etymology

Origin of reducer

First recorded in 1520–30; reduce + -er ¹

Example Sentences

Adding a safety warning based on flimsy evidence creates its own risks, such as deterring pregnant women from taking the pain killer and fever reducer when they need it.

From The Wall Street Journal • Oct. 29, 2025

Participating in Veganuary also appears to shift people's identity from seeing themselves as a meat eater to more of a "meat reducer" or "meat excluder".

From Salon • Jan. 2, 2025

The plant contains dozens of bioactive chemical compounds and is used throughout Southeast Asia and China as a painkiller, fever reducer, and diuretic.

From Science Magazine • May 1, 2024

Acetaminophen is considered the safest over-the-counter pain reliever and fever reducer available during pregnancy.

From Science Daily • Jan. 3, 2024

Reduction should take place gradually, and this is best accomplished with a weak reducer.

From Bromide Printing and Enlarging A Practical Guide to the Making of Bromide Prints by Contact and Bromide Enlarging by Daylight and Artificial Light, With the Toning of Bromide Prints and Enlargements by Tennant, John A.