train wheel
type of wheel specially designed for use on rail tracks
carrying wheels
a wheel that is not driven (uncoupled and can run freely, unlike a coupled or driving wheel);a running wheel and their axle may be called a carrying axle;referred to as leading wheel (at the front), or a trailing wheel (at the rear of the locomotive)
driving wheel
powered wheel of a railway locomotive
paper car wheel
composite wheels of North American railway carriages