noun pl. byssuses bys′·suses or byssi bys′si (-ī)

1. a fine fabric, esp. a linen cloth, used by the ancients, as in Egypt for mummy wrapping
2. Zool. a tuft of filaments, chemically similar to silk, secreted by various marine bivalves, esp. the mussels, and used to attach the mollusk to the substratum

Etymology: L < Gr byssos, fine linen or cotton < Sem, as in Heb buts < Sem *b-w-tz, to be white