bys·​sus | \ ˈbi-səs How to pronounce byssus (audio) \
plural byssuses or byssi\ ˈbi-​ˌsī How to pronounce byssi (audio) , -​(ˌ)sē \

Definition of byssus

1 : a fine probably linen cloth of ancient times
2 [New Latin, from Latin] : a tuft of long tough filaments by which some bivalve mollusks (such as mussels) adhere to a surface

First Known Use of byssus

14th century, in the meaning defined at sense 1

History and Etymology for byssus

Middle English bissus, from Latin byssus, from Greek byssos flax, of Semitic origin; akin to Hebrew būṣ linen cloth

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The first known use of byssus was in the 14th century

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Cite this Entry

“Byssus.” The Dictionary, Merriam-Webster Inc., Accessed 23 January 2020.

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out of the ordinary or unreasonable

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