Emily Dickinson Lexicon

floss, n. [Poss. from OFr flosche, down, pile of velvet; cf. L. flos, flower.]

1. Woven filaments; soft strands of a spider web; downy or silky substance in the husks of certain plants; word play on “Flower” and “Floss.”
2. Rough silk which envelops the cocoon of the silk worm.
3. Silk in fine filaments.