valance (n.)

piece of hanging, decorative drapery, mid-15c., of uncertain origin, probably from Anglo-French *valaunce, valence, from valer "go down, let down," variant of Old French avaler "descend, go down;" or possibly from the plural of Old French avalant, from present participle of avaler "go down." The notion is of something "hanging down." Not now considered to be from the name of Valence in southwestern France, which is from the Roman personal name Valentius. Related: Valenced.