单词：pelycosaurs
(pelycosaur 的复数) n.[古生]盘龙( 下孔亚纲类似哺乳类的一种爬行动物)
plural of pelycosaur
n large primitive reptile having a tall spinal sail; of the Permian or late Paleozoic in Europe and North America
n large primitive reptile having a tall spinal sail; of the Permian or late Paleozoic in Europe and North America