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Definition of Jake brake
1. Noun. (slang) Especially on trucks, an engine compression brake that closes the valves in an engine in order to slow the vehicle; an engine retarder. ¹
¹ Source: wiktionary.com
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1. Noun. (slang) Especially on trucks, an engine compression brake that closes the valves in an engine in order to slow the vehicle; an engine retarder. ¹
¹ Source: wiktionary.com