Pieces of metal, built into the joints of a wall, so as
   to lap over the edge of the gutters or to cover the edge of the
   roofing; also, similar pieces used to cover the valleys of roofs of
   slate, shingles, or the like. By extension, the metal covering of
   ridges and hips of roofs; also, in the United States, the protecting of
   angles and breaks in walls of frame houses with waterproof material,
   tarred paper, or the like. Cf. Filleting.