A rotating part of a mechanical device; for example, in an electric motor, generator, alternator, or pump.

(aviation) The wing of a helicopter or other rotary-wing aircraft.

(meteorology) A type of powerful horizontal-axis atmospheric vortex generated by the interaction of strong winds with mountainous terrain.

A quantity having magnitude, direction, and position.

(cellular automata) The set of cells within an oscillator that switch between being alive and dead over the course of the oscillator's period.