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

Aspidosperma excelsum, a tree native to Peru. / Trochodendron aralioides, a tree or large shrub native to Japan, Taiwan, and southern Korea.

A pinion with cylindrical staves, instead of teeth, inserted at their ends in two parallel disks or plates.

Alternative form of wheelhorse.

(US) Any assassin bug of the genus Arilus, large true bugs with wheel-shaped pronotal armor. They are predators upon soft-bodied insects.

Alternative form of daisywheel

A wheel whose rim and hub are connected by a continuous plate of metal, instead of by arms or spokes.

hamster wheel

Time moves forward; circumstances change; life continues.