radiator

American  

[rey-dee-ey-ter] / ˈreɪ diˌeɪ tər /

noun

1. a person or thing that radiates.

2. any of various heating devices, as a series or coil of pipes through which steam or hot water passes.

3. a device constructed from thin-walled tubes and metal fins, used for cooling circulating water, as in an automobile engine.

4. Radio. a transmitting antenna.

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radiator British  

/ ˈreɪdɪˌeɪtə /

noun

1. a device for heating a room, building, etc, consisting of a series of pipes through which hot water or steam passes

2. a device for cooling an internal-combustion engine, consisting of thin-walled tubes through which water passes. Heat is transferred from the water through the walls of the tubes to the airstream, which is created either by the motion of the vehicle or by a fan

3. an electric fire

4. electronics the part of an aerial or transmission line that radiates electromagnetic waves

5. an electric space heater

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radiator Scientific  

/ rā′dē-ā′tər /

1. A body that emits radiation. Radiators are commonly designed to transfer heat energy from one place to another, as in an automobile, in which the radiator cools the engine by transferring heat energy from the engine to the air, or in buildings, where radiators transfer heat energy from a furnace to the air and objects in the surrounding room.

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Etymology

Origin of radiator

First recorded in 1830–40; radiate + -or ²

Explanation

A room in an old house is often heated by a radiator, a metal device made up of pipes that circulate steam or hot water. If your house is heated with radiators, there will usually be one in each room, all connected to a central heating system. A radiator gets hot, and it sends that heat out into the room — in other words, it radiates heat. In fact, the word radiator originally meant "anything that radiates," including heat, light, or energy. By the 1850's, radiator had come to primarily mean "heater in a building or house."

Example Sentences

The outside air can be used to boil the refrigerant, allowing the cycle to repeat: the compressor squeezes it and makes it super-hot again, ready to heat more radiator water.

From BBC • Mar. 22, 2026

Your mother’s radiator strike is just one microexample of how consumers and economists are worried about the impact these latest events will have on the global oil supply, gas bills and the economy.

From MarketWatch • Mar. 4, 2026

A "closed-loop" water cooling system, which works a bit like a car radiator and does not require regular refills, prevents them from malfunctioning.

From Barron's • Feb. 26, 2026

I don’t know if he’s out of gas, has a busted radiator, flat tires or is suffering from dementia.

From Salon • Jan. 23, 2026

No thank you, I’d rather be stretched out on my favorite rug in front of a nice, whistling radiator.

From "Bunnicula" by Deborah Howe and James Howe

Related Words

• boiler
• fastball
• furnace
• oven
• stove