noun

coolant

KOO-luhnt

noun

A liquid or gas used to absorb and carry away heat from a machine or system.

"Check the coolant level in your car's radiator every few months."

"The reactor uses water as its coolant."

How to Use Coolant

Learner’s notes

In plain EnglishA fluid whose job is to soak up heat and keep an engine or machine from overheating.

Common pairings

engine coolant coolant leak top up the coolant

coolants plural

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Check the _____ level in your car's radiator every few months.

Built from cool plus the suffix -ant, which typically marks a substance that performs an action (compare "lubricant," "deodorant").