A pinwheel is a colorful toy that spins when wind blows against it. It has several blades, usually made of paper or plastic, attached to a stick. Each blade catches the wind like a tiny sail, making the whole thing whirl around in circles. You've probably seen kids holding pinwheels at carnivals or parades, watching them blur into a spinning rainbow.

Making a pinwheel is a classic craft project. You fold and cut paper into a square, then fold the corners toward the center and pin them to a stick or straw. The trick is leaving just enough room for the blades to spin freely. Some pinwheels have four blades; others have six or eight.

The word also describes anything arranged in a similar spinning pattern. Galaxies can form pinwheel shapes, with arms of stars spiraling out from the center. A pinwheel galaxy looks remarkably like the toy you might stick in your garden. Fireworks that spin and shoot sparks in all directions are called pinwheels too. And if you arrange sandwich slices in a circle with all the points meeting in the middle, you've created a pinwheel pattern on the plate.