* Rudolf Diesel (1858-1913) was a German engineer who invented the diesel engine.
* He patented his invention in 1892, and the engine quickly gained popularity due to its efficiency and power.
* The word "diesel" was first used in English in 1900, as a noun referring to the engine itself. It later came to be used as an adjective to describe anything related to the engine, such as diesel fuel or a diesel car.
Therefore, the etymology of the word "diesel" is simply a direct adoption of the inventor's name.