nummulitic limestone

noun

num·​mu·​lit·​ic limestone ˌnəm-yə-ˈli-tik- 

: the most widely distributed and distinctive formation of the Eocene in Europe, Asia, and northern Africa

Word History

Etymology

New Latin Nummulites, genus of foraminafers characteristic of such limestone (from Latin nummulus "coin" + New Latin -ītēs -ite entry 1) + -ic entry 1 — more at nummular

Note: The genus name Nummulites was introduced by J.B. lamarck in Système des animaux sans vertèbres (Paris, 1801), p. 101; Latin nummulus alludes to the coin-like shape of the fossils.

First Known Use

1830, in the meaning defined above