proostracum

noun

pro·​os·​tra·​cum
prōˈästrə̇kəm
plural proostraca
-kə
: the anterior horny or calcareous prolongation of the phragmocone of belemnites and related cephalopods

Word History

Etymology

New Latin, from pro- entry 1 + Greek ostrakon earthen vessel, potsherd, shell

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Dictionary Entries Near proostracum

proopic

proostracum

prootic

See More Nearby Entries 

Cite this Entry

“Proostracum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/proostracum. Accessed 22 Nov. 2024.

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