From Longman Dictionary of Contemporary Englishcoolantcoo‧lant /ˈkuːlənt/ noun [countable, uncountable] technical TEMa liquid or gas used to cool something, especially an engine
Examples from the Corpus
coolant• Their cars can undergo a potentially expensive conversion to the R-134a coolant that is being used in new cars.• Tritium is radioactive water used as a coolant in submarines' reactors.• The new fridge uses a mix of butane and propane gases as coolants.• Condenser coils are the tubes under or behind the refrigerator that carry coolant to the refrigeration unit.• The instruments were shattered, but the controls and engine were functioning except the latter was spewing coolant vapour.• All the coolant hit the engine block in a tumult of steam.• The coolant could then be circulated back into the command module.• This coolant can be bought without a license for as little as $ 3 a pound. 