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

See Examples For:

reducer reducers

Some scientists have said that warnings against acetaminophen are premature, because the drug is the only fever reducer recommended to women at some points in pregnancy.

From The Wall Street Journal ● Sep. 22, 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

The Second element is the reducer, in which by an independent process the reduction of the carbonic-acid gas, the dissociation of the steam, and the transformation of the hydrocarbons takes place.

From Gas-Engines and Producer-Gas Plants A Practice Treatise Setting Forth the Principles of Gas-Engines and Producer Design, the Selection and Installation of an Engine, Conditions of Perfect Operation, Producer-Gas Engines and Their Possibilities, the Care of Gas-Engines and Producer-Gas Plants, with a Chapter on Volatile Hydrocarbon and Oil Engines by R. E. Mathot

“The second is the component layer beneath them, the motors, reducers, bearings, sensors, and power content inside the machines themselves.”

From Barron's ● Jun. 30, 2026

The first winners may be the companies supplying actuators, reducers, sensors, machine vision, batteries, motion-control systems and industrial software.

From MarketWatch ● May 27, 2026

The components include sensors, so-called coreless motors that power precise high-speed movements and speed reducers often used in joints to mimic human motions.

From The Wall Street Journal ● Apr. 3, 2026

Glen Calder expected a shipment of gearbox reducers needed to build a particular model of his company's paving machines last week.

From Reuters ● Dec. 23, 2022

Boston power transmission products from stock, gears, speed reducers.

From U.S. Copyright Renewals, 1961 January - June by Library of Congress. Copyright Office