visor (
http://definr.com/visor)
n 1: a piece of armor plate (with eye slits) fixed or hinged to a
medieval helmet to protect the face [syn:
vizor]
2: a brim that projects to the front to shade the eyes; "he
pulled down the bill of his cap and trudged ahead" [syn:
bill,
peak,
eyeshade,
vizor]