coolant

noun

cool·​ant ˈkü-lənt How to pronounce coolant (audio)
: a usually fluid cooling agent

Examples of coolant in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
By introducing the boron-containing material into the reactor coolant during an emergency, the system is designed to reduce the number of neutrons available to sustain the nuclear reaction. — Neetika Walter, Interesting Engineering, 1 Sep. 2026 Marquez says to check the level of coolant, which keeps the car from getting too hot in the summer, only when the engine is cold. — Lois K. Solomon, Sun Sentinel, 22 Aug. 2026 Mixing different coolant chemistries can reduce corrosion protection and shorten coolant life. — John Paul Senior Manager Public Affairs and Traffic Safety Aaa Northeast, Hartford Courant, 15 Aug. 2026 See All Example Sentences for coolant

Word History

Etymology

cool entry 2 + -ant entry 1

First Known Use

1915, in the meaning defined above

Time Traveler
The first known use of coolant was in 1915

Rhymes for coolant

See All Rhymes for coolant

Browse Nearby Words

coolamon
coolant
cool bath
See all Nearby Words

Cite this Entry

“Coolant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/coolant. Accessed 4 Sep. 2026.

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Kids Definition

coolant

noun
cool·​ant ˈkü-lənt How to pronounce coolant (audio)
: a usually fluid cooling substance

More from Merriam-Webster on coolant

Britannica.com: Encyclopedia article about coolant

Last Updated: - Updated example sentences
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