[ˈiːə(ʊ)siːn], (Adjective)

Definitions:
- relating to or denoting the second epoch of the Tertiary period, between the Palaeocene and Oligocene epochs
(e.g: similar patterns have been documented in North American mammals across the late Eocene extinction)


Phrases:

Origin:
mid 19th century: from Greek ēōs ‘dawn’ + kainos ‘new’

[ˈiːə(ʊ)siːn], (Noun)

Definitions:
- the second epoch of the Tertiary period, or the system of rocks deposited during it
(e.g: a very minor extinction occurred at the end of the middle Eocene)


Phrases:

Origin:
mid 19th century: from Greek ēōs ‘dawn’ + kainos ‘new’