Byssus :: Byssus (n.) A cloth of exceedingly fine texture, used by the ancients. It is disputed whether it was of cotton, linen, or silk..
Byssus :: Byssus (n.) A tuft of long, tough filaments which are formed in a groove of the foot, and issue from between the valves of certain bivalve mollusks, as the Pinna and Mytilus, by which they attach themselves to rocks, etc..
Byssus :: Byssus (n.) An obsolete name for certain fungi composed of slender threads.