A racetrack is a specially designed course where people compete to see who can go the fastest. The most familiar kind is an oval track where cars race around and around, like the Indianapolis Motor Speedway where drivers reach speeds over 200 miles per hour. Horse racing tracks are similar ovals, usually covered in dirt or grass, where horses and their jockeys thunder past cheering crowds.

Racetracks exist for almost anything that moves: motorcycles, go-karts, bicycles, even dogs and camels in some parts of the world. Some tracks are simple circles, while others wind through challenging curves and hills. Formula One cars race on twisting road courses that test a driver's skill through hairpin turns and straightaways.

The word can also describe any route where racing happens. A racetrack might be marked out temporarily on city streets, like the famous Monaco Grand Prix, or it could be a downhill ski course where racers compete for the best time. When someone drives recklessly fast on a regular road, you might hear people complain that they're “treating the highway like a racetrack,” meaning they're driving dangerously where they shouldn't be racing at all.