A doughnut, or donut, is a sweet deep-fried piece of dough or batter. The two most common types are the torus-shaped ring doughnut, and the filled doughnut, a flattened sphere injected with jam/jelly, cream, custard, or another sweet filling. A small spherical piece of dough, originally made from the middle of a ring doughnut, can be cooked as a doughnut hole.
A doughnut or donut is a maneuver performed while driving an automobile. Performing this maneuver entails rotating the rear of the automobile around the front wheels in a continuous motion, creating (ideally) a circular skid-mark pattern of rubber on a roadway and also causing the tires to smoke considerably.