What term describes a white marking around the upper part of the horse's foot?

The term that describes a white marking around the upper part of the horse's foot is known as a "sock." This marking typically covers the lower part of the leg, adjacent to the hoof, and can vary in size and appearance. Socks are often seen on horses and are used in identification, showcasing a distinctive pattern that can help distinguish one horse from another.

The other terms provided refer to different types of markings or anatomical features. The coronet, for example, refers to the area around the top of the hoof, just below the hairline, while a half pastern is a white marking that extends partially up the pastern, above the hoof but not reaching the area of the coronet. A star typically describes a small white marking on the horse's forehead. Each of these markings contributes to identifying characteristics in horses, but the specific marking around the upper part of the horse's foot is accurately termed a sock.