Word forms: (regular plural) gear trains
noun (Automotive engineering: Vehicle components, Engine, transmission, and exhaust) A gear train is a series of gears designed to achieve a particular overall gear ratio. ⇒ A simple gear train has only one gear fixed to each shaft. ⇒ A gear train consists of a combination of two or more gears, mounted on rotating shafts, to transmit torque or power. ⇒ A compound gear train will have more than one gear fixed to some of the shafts.
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