Rudista

plural noun

Ru·​dis·​ta

rüˈdistə

in some classifications

: a division of Eulamellibranchia comprising extinct chiefly Cretaceous bivalve mollusks with one valve elongate, conical, and thick-shelled and the other small and fitting like a lid on the first

rudistan

(ˈ)⸗¦⸗stən

adjective or noun

rudistid

(ˈ)⸗¦⸗stə̇d

adjective or noun

Word History

Etymology

New Latin, from Latin rudis rude, raw + -ista -ist

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