plural noun

: 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


New Latin, from Nummulites, type genus + -idae

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Dictionary Entries Near Nummulitidae

Cite this Entry

“Nummulitidae.” Dictionary, Merriam-Webster, Accessed 22 Apr. 2024.

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