(Christian Karl) (1858-1913) German engineer who patented the diesel engine. He began his career as a refrigerator engineer and, like many engineers of the period, sought to develop a better power source than the conventional steam engine. Able to operate with greater efficiency and economy, the diesel engine soon found a ready market.
Born in Paris, Diesel moved to Germany after the outbreak of the Franco-Prussian War 1870, and studied at Munich Polytechnic.
His ideas for an engine where the combustion would be carried out within the cylinder were first published 1893, one year after he had taken out his first patent. In his first engine, Diesel is thought to have used coal dust as a fuel, but he later discarded this along with several other types in favor of a form of refined mineral oil. A very high pressure must be used to compress the air before fuel injection, and he was nearly killed when a cylinder head blew off one of his prototype engines. In 1899, he founded his own manufacturing company in Augsburg.

1. Diesel engine
2. A vehicle driven by a diesel engine
3. Diesel fuel

An internal-combustion engine that burns heavy oil; Also called: diesel, diesel engine, diesel motor.