Facial hair reaching from the top of the head down the side of the face to the side of the chin
If a man has sideburns, he has a strip of hair growing down the side of each cheek. a young man with long sideburns. hair grown down the sides of a man's face in front of his ears (burnsides type of beard in which the chin is shaved, from Ambrose Burnside (1824-81), U.S. general who wore such a beard)