also Diesel, type of internal combustion engine, 1894, named for Rudolf Diesel (1858-1913), German mechanical engineer who designed this type of engine.
From 1650s as "moving from place to place;" by 1814 as "having the power of moving by itself. The noun meaning "engine which travels on rails by its own power" is from 1829, short for locomotive engine, which is attested from 1814. A locomotive engine used without rails was a traction engine, which became tractor.
1819, "ten-legged animal, type of crustacean having ten legs" (crabs, lobsters, shrimp), from French décapode (1806), from Modern Latin Decapoda (animalia), from Greek dekapoda, neuter plural of dekapous "ten-footed" (see ten + foot (n.)). From 1885 in reference to a type of locomotive with ten driving-wheels.