periostracum

noun

peri·​os·​tra·​cum
ˌperēˈästrəkəm
plural periostraca
-kə
: a chitinous layer covering the exterior of the shell in many mollusks, being usually well developed in freshwater forms, and serving to protect the shell from corrosion

Word History

Etymology

New Latin, from peri- + Greek ostrakon shell

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Dictionary Entries Near periostracum

periostracal

periostracum

peripatetic

See More Nearby Entries 

Cite this Entry

“Periostracum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/periostracum. Accessed 29 Nov. 2024.

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