noun
challis
SHAL-ee/ʃˈæli/
A soft, lightweight fabric used for clothing.
The floral challis drapes in soft folds beside a matching scarf.

Etymology
The fabric's name is of unknown origin, perhaps from a surname. It is said to have first been manufactured at Norwich as a fine fabric for dresses.
In context
cotton crepe machine, drapey rayon challis, pil- uh silk poly charmeuse, silk poly rayon crepe de chine. They're specific. Um she's going lightweight, drapey to somewhat structured,