bys·sus (bĭs'əs) n.
pl.bys·sus·es or bys·si (bĭs'ī')
Zoology A mass of strong, silky filaments by which certain bivalve mollusks, such as mussels, attach themselves to rocks and other fixed surfaces.
A fine-textured linen of ancient times, used by the Egyptians for wrapping mummies.
[Middle English bissus, linen cloth, from Latin, from Greek bussos, linen; akin to Sanskrit picuḥ, cotton (of Dravidian origin), or ultimately from Egyptian w'ḏ, linen.] bys'sal (bĭs'əl) adj.