EOCENE

Eocene, Eocene epoch

(noun) from 58 million to 40 million years ago; presence of modern mammals

Source: WordNet® 3.1

Etymology

Adjective

Eocene (comparative more Eocene, superlative most Eocene)

(geology) of a geologic epoch within the Paleogene period from about 56 to 34 million years ago.

Proper noun

Eocene

(geology) the Eocene epoch

Source: Wiktionary

E"o*cene, a. Etym: [Gr. (Geol.)

Definition: Pertaining to the first in time of the three subdivisions into which the Tertiary formation is divided by geologists, and alluding to the approximation in its life to that of the present era; as, Eocene deposits.

– n.

Definition: The Eocene formation. Lyell.

Source: Webster’s Unabridged Dictionary 1913 Edition