A colt is a young male horse, typically under four years old. On ranches and farms, people watch colts carefully as they grow, since these energetic youngsters are still learning and often haven't been trained to carry riders yet. Colts gallop and play in pastures, building the strength and coordination they'll need as adult horses.

Female horses of the same age are called fillies. Once a colt reaches about four years old, he may be called a stallion if he is not castrated, or a gelding if he is.

You might also hear “colt” used as a metaphor for someone young and energetic who's still learning. A rookie baseball player joining a professional team might be called a colt, suggesting he has potential but needs experience.