While the ordinary-language usage has a pejorative valance, it is an adaptive function.
Evidence has been mounting in the past few years that xenon, as well as other members of zero valance elements, do form compounds.
The catalyzed cementation chemistry centers around the use of zero valance iron.
Awnings shall have a loose valance, and should generally be located to fit within window or door recesses.
British Dictionary definitions for valance
valance
/ˈvæləns/
noun
1.
a short piece of drapery hung along a shelf, canopy, or bed, or across a window, to hide structural detail
Derived Forms
valanced, adjective
Word Origin
C15: perhaps named after Valence, France, town noted for its textiles
Word Origin and History for valance
n.
piece of drapery, mid-15c., from Anglo-French *valance, from valer "go down," variant of Old French avaler; or possibly from the plural of Old French avalant, from present participle of avaler "go down." The notion is of something "hanging down."