Nummulitidae

plural noun

Num·​mu·​lit·​i·​dae

ˌnəmyəˈlitəˌdē

: a family of foraminifers that are mostly extinct, have a calcareous symmetrical usually lenticular or discoidal shell composed of numerous chambers spirally or concentrically arranged, and form whole strata in some Eocene and Oligocene deposits of eastern and southern Asia and the Mediterranean region from their shelly remains

Word History

Etymology

New Latin, from Nummulites, type genus + -idae

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