A rotary engine

Engine is from the Latin ingenium, which referred to one’s ability to create things; it comes from a root meaning ‘create; beget’. Its first meaning in English, from about the fourteenth century, was very much this one of genius, a skill in devising things. It could also refer to a contrivance or device, particularly any mechanical apparatus. In the 1670s one John Worlidge invented a machine for pulping apples in cidermaking; he termed his device the Ingenio, an obvious reference to the Latin original. Engine was commonly applied also to weapons of war.