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.
Instead of high-pressure water, this reactor uses pure liquid lead as its primary coolant. — Aman Tripathi, Interesting Engineering, 7 Aug. 2026 The Danube has fallen to record lows after successive European heatwaves, wreaking havoc on both Romanian and Hungarian reactors that rely on the river for coolant. — semafor.com, 5 Aug. 2026 When the performance finished, those technicians rushed to spray their now sizzling lidar with coolant following that four-minute exertion. — Charlie Campbell, Time, 23 July 2026 Commercial refrigerators and air conditioners were going to transition to new, less damaging coolants, which are available. — Blanca Begert, Los Angeles Times, 21 July 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 12 Aug. 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

Nglish: Translation of coolant for Spanish Speakers

Britannica.com: Encyclopedia article about coolant

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