Source : Webster's Revised Unabridged Dictionary (1913)

Cornice \Cor"nice\ (k?r"n?s), n. [F. corniche, It. cornice, LL.
   coronix, cornix, fr. L. coronis a curved line, a flourish
   with the pen at the end of a book or chapter, Gr. ???; akin
   to L. corona crown. sEE {Crown}, and cf. {Coronis}.] (Arch.)
   Any horizontal, molded or otherwise decorated projection
   which crowns or finishes the part to which it is affixed; as,
   the cornice of an order, pedestal, door, window, or house.
   --Gwilt.

   {Cornice ring}, the ring on a cannon next behind the muzzle
      ring.

Source : WordNet®

cornice
     n 1: a decorative framework to conceal curtain fixtures at the
          top of a window casing [syn: {valance}, {valance board},
           {pelmet}]
     2: a molding at the corner between the ceiling and the top of a
        wall
     3: the topmost projecting part of an entablature
     v : furnish with a cornice