Rotary (adjective)

1. Moving in a circular or rotating manner.
2. Having a circular shape or design.
3. Relating to or being a club or organization that meets regularly and whose members take turns serving as officer.

Origin:

Rotary, from latin rotarius of or for turning, from rota wheel.

Examples:

1. The rotary dial on the phone.
2. The rotary motion of the wheel.
3. The rotary club meets every week.
4. The rotary cutter is a useful tool for quilting.
5. The rotary engine is a type of internal combustion engine.