engine (n.) Look up engine at Dictionary.com
c.1300, "mechanical device," also "skill, craft," from Old French engin "skill, cleverness," also "trick, deceit, stratagem; war machine" (12c.), from Latin ingenium "inborn qualities, talent" (see ingenious). At first meaning a trick or device, or any machine (especially military); sense of "device that converts energy to mechanical power" is 18c., especially of steam engines.