A device for measuring distance, consisting of a wheel of fixed circumference, a handle, and a clicking device triggered by each revolution of the wheel.

In water-powered mills, a horizontal water wheel used to power a grinding stone set in a tub; usually in the form of a short cylinder turned by the impact of one or more streams of water striking against vanes attached radially to the wheel.

A gear wheel that revolves around the wheel with which it meshes, in an epicyclic train.

(engineering) A form of cam shaped like a heart, used to convert uniform rotary motion into uniform reciprocating motion.

Any sea urchin of the genus Rotula having a round, flat shell; a type of sand dollar.

A symbol of indigenous North American culture and religion. / A stone monument related to this symbol, constructed by laying stones in a particular pattern on the ground oriented to the four directions.

(circus) A hollow wheel larger than a person, attached to and suspended from an axle, and inside of which an artist performs.

A type of hubcap or inner wheel ornament that spins independently inside of a wheel itself when the vehicle is in motion, and continues to spin once the vehicle has come to a stop.

Ferris wheel

A gear arrangement consisting of a screw (the worm) whose thread meshes with a gear wheel in such a way as to turn the direction of drive through a right angle.