1.鳍足类的
1.鳍足动物
1.a sea mammal that has a streamlined body and four flippers and eats fish and other meat, e.g. a walrus, sea lion, or seal.
1.The legs were strong and ended in long feet very much like those of a modern pinniped.
它的后肢很强壮,底部有长足,非常像现在的鳍足类动物。