Palaeogene
adjective geology UK specialized ( US Paleogene) uk/ˈpæl.i.ə.dʒiːn/ us/ˈpeɪ.li.oʊ.dʒiːn/
古第三纪的（迄今6600万至2300万年前）
from or referring to the period of time between about 66 and 23 million years ago, in which many insects, mammals, and birds appeared
the Palaeogene period 古第三纪
Palaeogene flora and fauna 古第三纪动植物
the Palaeogene
noun [ S ]
古第三纪
the Palaeogene period