n. 渐新世, 渐新统

a. 渐新世的, 渐新统的

[ noun ]
from 40 million to 25 million years ago; appearance of sabertoothed cats
<noun.time>

Oligocene \Ol"i*go*cene\, a. [Oligo- + Gr. ? new, recent.]
(Geol.)
Of, pertaining to, or designating, certain strata which
occupy an intermediate position between the Eocene and
Miocene periods. -- n. The Oligocene period. See the Chart of
{Geology}.