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

The Gibraltar arc formed in the Oligocene as a part of the Western Mediterranean subduction zones.

From Science Daily

It represents a segment of a population tracing its ancestry back to the widespread Oligocene ancestor, approximately 28 million years ago, in the Philippines.

From Science Daily

The report includes an understated, but nonetheless pointed, criticism of the paltriness of scientific literature about North Pacific odontocetes species from the Oligocene epoch, which lasted roughly from 33.7 to 23.8 million years ago.

From Salon

As the Eocene gave way to the Oligocene, tectonic forces dealt a final blow to Gondwana, cleaving apart Australia, South America and Antarctica.

From Scientific American

Based on the location and age of the rocks surrounding the ant hills, the researchers estimate that the fossils are from the late Eocene and early Oligocene epochs.

From New York Times