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
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Then hydrogen leaks arose during the third rehearsal, which led to NASA not only changing the way in which liquid hydrogen is loaded, but also modifying the ground umbilical plates that send power, coolant, fuel and communications to the rocket, according to Blackwell-Thompson. Elizabeth Howell, Space.com, 23 Jan. 2026 The main challenge has been poor heat transfer, which prevents solid coolants from working efficiently at scale. Neetika Walter, Interesting Engineering, 22 Jan. 2026 Signs of an issue could include coolant spots on the ground, loss of cabin heat, powertrain unit overheating or a warning for a low coolant level, the documents noted. Clara McMichael, ABC News, 21 Jan. 2026 AutoZone recommends checking fluid levels, such as oil, brake fluid and coolant to ensure the vehicle can handle low temperature and prevents your engine from freezing. Isa Almeida, Oklahoman, 21 Jan. 2026 See All Example Sentences for coolant

Word History

First Known Use

1915, in the meaning defined above

Time Traveler
The first known use of coolant was in 1915

Browse Nearby Words

Cite this Entry

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

Kids Definition

coolant

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

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