What is the meaning of Wheel?

A circular frame turning about an axis; a rotating disk, whether solid, or a frame composed of an outer rim, spokes or radii, and a central hub or nave, in which is inserted the axle, -- used for supporting and conveying vehicles, in machinery, and for various purposes; as, the wheel of a wagon, of a locomotive, of a mill, of a watch, etc.

Source: Webster’s Revised Unabridged Dictionary (1913), via OPTED