From WordNet (r) 3.0 (2006) [wn]:
cornice
n 1: a decorative framework to conceal curtain fixtures at the
top of a window casing [syn: cornice, 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 1: furnish with a cornice
From The Collaborative International Dictionary of English v.0.48 [gcide]:
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.
[1913 Webster]
Cornice ring, the ring on a cannon next behind the muzzle
ring.
[1913 Webster]