Definition of byssus in English:

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Pronunciation: /ˈbɪsəs/

noun (plural byssuses or byssi /ˈbɪsʌɪ/)

1 [mass noun] historical A fine textile fibre and fabric of flax.
Example sentences
  • Exactly how these proteins link together to give the material, called byssus, its strength has remained unclear.
  • The word denotes Egyptian linen of peculiar whiteness and fineness (byssus).
  • If we understand it of thread, it may refer to the byssus or fine flax for which Egypt was famous; but I do not see on what authority we translate it linen thread.
2 Zoology A tuft of tough silky filaments by which mussels and some other bivalves adhere to rocks and other objects.
Example sentences
  • Before serving them to the knots, we put the mussels through a mesh to break the byssus threads that held them together and to sort them by size.
  • The primary source of this variation is not the number of threads present in the byssus, but rather, their thickness.
  • The strength of the entire byssus is expected to be proportional to the number of threads times the average strength of each thread.



Example sentences
  • The mechanical behavior of byssal threads is therefore complex, and it can be somewhat perplexing as to what function many of these unusual properties serve.
  • Mussels in the top layers have difficulty accessing primary substrate and must instead attach byssal threads to neighboring shells.
  • As the right valve of the species, and accordingly the structure of its byssal area is unknown, its generic affiliation remains uncertain.


Late Middle English: from Latin, from Greek bussos, of Semitic origin.

For editors and proofreaders

Line breaks: bys¦sus

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