D defs.my
Entry 1 sense Webster, 1913

Diesel

/(dē"zel)/ · IPA /ˈdisəl/
01 A type of internal-combustion engine in which the air drawn in by the suction stroke is so highly compressed that the heat generated ignite…
  1. 1.
    A type of internal-combustion engine in which the air drawn in by the suction stroke is so highly compressed that the heat generated ignites the fuel (usually a heavy oil), the fuel being automatically sprayed into the cylinder under pressure. The Diesel engine has a very high thermal efficiency.