1: one that imparts motion; specifically : prime mover
2: any of various power units that develop energy or impart motion: as
a : a small compact engine
b : internal combustion engine; especially : a gasoline engine
c : a rotating machine that transforms electrical energy into mechanical energy.
History of motorcycle
: American, Sylvester Howard Roper (1823-1896) invented a two-cylinder, steam-engine motorcycle (powered by coal) in 1867....German, Gottlieb Daimler invented the first gas-engined motorcycle in 1885, which was an engine attached to a wooden bike.....However, inventors such as William Harley and the Davidsons brothers continued to develop motorcycles and their business competitors were other new start-up companies such as Excelsior, Indian, Pierce, Merkel, Schickel and Thor.
So far I'm figuring that the Indian is the only true enginecycle.