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Synonyms

heater

American  
[hee-ter] / ˈhi tər /

noun

  1. any of various apparatus for heating, especially for heating water or the air in a room.

  2. Electronics. the element of a vacuum tube that carries the current for heating a cathode.

  3. Slang. a pistol, revolver, or other firearm.

heater British  
/ ˈhiːtə /

noun

  1. any device for supplying heat, such as a hot-air blower, radiator, convector, etc

  2. slang a pistol

  3. electronics a conductor carrying a current that indirectly heats the cathode in some types of valve

"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

  • reheater noun

Etymology

Origin of heater

First recorded in 1490–1500; heat + -er 1

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.

Astronaut Christina Koch said the so-called Universal Waste Management System was giving off "a burning heater smell."

From Barron's • Apr. 9, 2026

The charity Community Action Northumberland suggested switching to an oil-filled electric radiator or electric heater to help with costs.

From BBC • Mar. 26, 2026

Warming your body with toasty cables against your shirt is far more energy-efficient than a space heater, though probably not as convenient on a Zoom call.

From The Wall Street Journal • Jan. 23, 2026

"Tea, coffee, cookies, wafers, water are free," she said, adding that staff were keeping a coal-fired heater burning "round the clock".

From Barron's • Jan. 22, 2026

I poured the slurry in a dish and then set it underneath the water heater to dry.

From "October Sky" by Homer Hickam

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

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.