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blowby

noun

blow·​by ˈblō-ˌbī How to pronounce blowby (audio)
: leakage of combustion gases between a piston and the cylinder wall into the crankcase in an automobile

Word History

First Known Use

1908, in the meaning defined above

Time Traveler
The first known use of blowby was in 1908

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Cite this Entry

“Blowby.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/blowby. Accessed 3 Dec. 2025.

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