A large, coin-shaped, fossil foraminifer of the genus Nummulites, widely distributed in limestone formations from the Eocene Epoch to the Miocene Epoch of the Cenozoic.
[From New Latin Nummulītēs, type genus, from Latin nummulus, diminutive of nummus, coin, probably from Greek nomimos, customary, legal; see nem- in the Appendix of Indo-European roots.]
num′mu·litic (-lĭtĭk) adj.
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