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en·gine /ˈɛndʒən/ Pronunciation Key - Show Spelled Pronunciation[en-juhn] Pronunciation Key - Show IPA Pronunciation
–noun
1. a machine for converting thermal energy into mechanical energy or power to produce force and motion.
2. a railroad locomotive.
3. a fire engine.
4. any mechanical contrivance.
5. a machine or instrument used in warfare, as a battering ram, catapult, or piece of artillery.
6. Obsolete. an instrument of torture, esp. the rack.
[Origin: 1250–1300; ME engin < AF, OF < L ingenium nature, innate quality, esp. mental power, hence a clever invention, equiv. to in- in-2 + -genium, equiv. to gen- begetting (see kin) + -ium -ium]
I see nothing in there about cars. First definition is too general, and the rest of them have nothing to do with what you are talking about. Who is the hick now?