a child's toy consisting of a wheel or leaflike curls of paper or plastic loosely attached by a pin to a stick, designed to revolve when blown by or as by the wind.
Also calleda kind of firework supported on a pin which, when ignited, revolves rapidly and gives a dazzling display of light.
a wheel having pins at right angles to its rim for engaging the teeth of a gear.
—v.i.
to revolve rapidly like a pinwheel: Images of the past pinwheeled through his mind.