The Collaborative International Dictionary of English v.0.48:

Valance \Val"ance\, v. t. [imp. & p. p. Valanced; p. pr. & vb.
   n. Valancing.]
   To furnish with a valance; to decorate with hangings or
   drapery.
   [1913 Webster]

         His old fringed chair valanced around with
         party-colored worsted bobs.              --Sterne.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Valance \Val"ance\, n. [Perhaps fr. OF. avalant descending,
   hanging down, p. pr. of avaler to go down, let down, descend
   (cf. Avalanche); but probably from the town of Valence in
   France.]
   [1913 Webster]
   1. Hanging drapery for a bed, couch, window, or the like,
      especially that which hangs around a bedstead, from the
      bed to the floor. [Written also valence.]
      [1913 Webster]

            Valance of Venice gold in needlework. --Shak.
      [1913 Webster]

   2. The drooping edging of the lid of a trunk, which covers
      the joint when the lid is closed.
      [1913 Webster]

WordNet (r) 3.0 (2006):

valance
    n 1: a decorative framework to conceal curtain fixtures at the
         top of a window casing [syn: cornice, valance, valance
         board, pelmet]

Moby Thesaurus II by Grady Ward, 1.0:

21 Moby Thesaurus words for "valance":
   beading, binding, bordering, bordure, edging, fimbria, fimbriation,
   flounce, frill, frilling, fringe, furbelow, galloon, hem, list,
   motif, ruffle, selvage, skirting, trimming, welt