prayer wheel

(engineering) One of a set of wheels of different sizes and number of teeth, that may be changed or substituted for one another in machinery, to produce a different but definite rate of angular velocity in an axis, as in cutting screws, gear, etc.

A noria.

(horology) The wheel of an escapement.

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

Ferris wheel

A stitch resembling a spider's web, worked into the material, and not over an open space.

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

A variety of bournonite with wheel-shaped twin crystals.

Alternative form of wheelhorse.