The brow ridge or supraorbital ridge is the bony protrusion of the upper eye socket. Its function is to protect the eyes and acts as a reinforcement for the eye socket itself against fracture.
The term supraorbital rim is ambiguous as it may refer to either the outer protrusion of the supraorbital ridge, or the supraorbital margin.
Males, compared to females, generally have more protrusive supraorbital rims. It's a feature of facial masculinity.