Oligocene

[ ol-i-goh-seen ]

adjective

1. noting or pertaining to an epoch of the Tertiary Period, occurring from 40 to 25 million years ago.

noun

1. the Oligocene Epoch or Series.

Oligocene

/ ɒˈlɪɡ-; ˈɒlɪɡəʊˌsiːn /

adjective

1. of, denoting, or formed in the third epoch of the Tertiary period, which lasted for 10 000 000 years

noun

1. the Oligocene
   the Oligocene epoch or rock series

Oligocene

/ ŏl′ĭ-gō-sēn′ /

1. The third epoch of the Tertiary Period, from about 37 to 24 million years ago. During this time there was an increase in volcanic activity, and Australia and South America separated from Antarctica. The climate started to cool and a glacier started to form in Antarctica. Modern mammalian groups continued to develop, and the first cats, dogs, horses, and related mammals appeared. Artiodactyls (even-toed ungulates) took over from the perissodactyls (uneven-toed ungulates) as the dominant medium-sized herbivores. Many types of grass also first appeared at this time.
2. See Chart at geologic time

Other Words From

• post-Oli·go·cene adjective

Word History and Origins

Origin of Oligocene¹

First recorded in 1855–60; oligo- + -cene

Word History and Origins

Origin of Oligocene¹

C19: oligo- + -cene

Example Sentences

Heteromyids are known from the Chadron formation, of early Oligocene age, in which a single tooth was found.

From Project Gutenberg

The Oligocene division has been generally accepted as a distinct period, but “Paleocene” is not so widely used.

From Project Gutenberg

A new species of the rodent Pipestoneomys from the Oligocene of Nebraska.

From Project Gutenberg

A soricid and two erinaceids from the White River Oligocene.

From Project Gutenberg

Its fauna is incompletely known; probably it is of Miocene or Oligocene origin.

From Project Gutenberg