A pinwheel is a spinning toy that looks like a flower on a stick. Blow on it or run through the garden with one and watch it spin. Some things, like peppermints, have a pinwheel pattern.
A pinwheel is a stick with twisted paper or plastic pieces that turn as they catch the wind. The original pinwheel, first called a whirligig, was invented in the nineteenth century by a woman who imagined children running while holding them in the air, which is exactly how pinwheels are usually played with. Before the toy, a pinwheel was a gear in a train's mechanism, and also a spinning firework also called a Catherine wheel.