coolant

American  

[koo-luhnt] / ˈku lənt /

noun

1. a substance, usually a liquid or a gas, used to reduce the temperature of a system below a specified value by conducting away the heat produced in the operation of the system, as the liquid in an automobile cooling system or the fluid that removes heat from the core of a nuclear reactor.

2. a lubricant that dissipates the heat caused by friction.

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coolant British  

/ ˈkuːlənt /

noun

1. a fluid used to cool a system or to transfer heat from one part of it to another

2. a liquid, such as an emulsion of oil, water, and soft soap, used to lubricate and cool the workpiece and cutting tool during machining

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Etymology

Origin of coolant

First recorded in 1925–30; cool + -ant

Example Sentences

Coolant can leak from the block heater and come in contact with the cable terminals, possibly causing a fire.

From Seattle Times • Jul. 8, 2021

Coolant spurted out of the valve, covering the floor with 80,000 gallons of highly radioactive water.

From Washington Times • May 30, 2017

Coolant seeps out of discarded equipment in landfills.

From New York Times • Nov. 23, 2012

Shan Nair, a nuclear safety expert who spent 20 years analyzing the consequences of Loss of Coolant Accidents like the one at Fukushima, discussed this factor on TIME's Econcentric blog.

From Salon • Mar. 18, 2011

To start with, drain the old coolant and replace it with something like Liquid Performance Racing Coolant, High Lifter Liquid Cool, or Redline Water Wetter.

From Time Magazine Archive