water jacket


: an outer casing which holds water or through which water circulates to cool the interior
specifically : the enclosed space surrounding the cylinder block of an internal combustion engine and containing the cooling liquid

Word History

First Known Use

1841, in the meaning defined above

Time Traveler
The first known use of water jacket was in 1841

Dictionary Entries Near water jacket

Cite this Entry

“Water jacket.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/water%20jacket. Accessed 4 Jun. 2023.

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