n. pl. bys·sus·es or bys·si (bĭsī′)
1. Zoology A mass of strong, silky filaments by which certain bivalve mollusks, such as mussels, attach themselves to rocks and other fixed surfaces.
2. 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.]
byssal (bĭsəl) adj.
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.