Oligocene

adj. of the oligocene period (geological period characterized by the presence of saber-toothed cats)

n. epoch in the Tertiary period characterized by the presence of saber-toothed cats (Geology)

The Oligocene epoch is a geologic period that extends from about 33.9 million to 23 million years before the present. As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly uncertain. The name Oligocene comes from the Greek (oligos, few) and (kainos, new), and refers to the sparsity of additional modern mammalian faunas after a burst of evolution during the Eocene. The Oligocene follows the Eocene epoch and is followed by the Miocene epoch. The Oligocene is the third and final epoch of the Palaeogene period.
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Noun
1. from 40 million to 25 million years ago; appearance of sabertoothed cats
(synonym) Oligocene epoch
(hypernym) epoch
(part-holonym) Tertiary, Tertiary period

adj. Oligocene, of the oligocene period (geological period characterized by the presence of saber-toothed cats)

n. Oligocene, epoch in the Tertiary period characterized by the presence of saber-toothed cats (Geology)

(n.)
The Oligocene period. See the Chart of Geology.
  

(a.)
Of, pertaining to, or designating, certain strata which occupy an intermediate position between the Eocene and Miocene periods.