(1)象牙質の牙と厚い脂肪層を持つ2種類の大型の北方海洋哺乳動物の内の一方
(2)either of two large northern marine mammals having ivory tusks and tough hide over thick blubber
さらに詳しく
(1)5本足指の厚皮動物
(2)five-toed pachyderm
