Which term describes a broad stripe that may extend around the eyes and down to the upper lip?

The term that describes a broad stripe that may extend around the eyes and down to the upper lip is "Blaze." In equine terminology, a blaze commonly refers to a distinct facial marking that is usually wider than a strip and can encompass a larger area on the horse's face. It often extends from the forehead or between the eyes and can go down to the muzzle or upper lip, giving it that characteristic broad stripe appearance.

In contrast, the other terms refer to different types of markings: a coronet refers to a narrow band of white around the hoof, as seen in certain breeds; a sock designates a white marking that typically covers the lower part of a horse's leg, often stopping just above the fetlock; and a half pastern is used to describe a white marking that extends up to the pastern area but does not cover the entire leg. Understanding these specific descriptors helps in identifying and describing markings on horses accurately.