n.

1. 【魚】白色大鱘魚
2. 【動】（北冰洋產的）白鯨

n.

1. a small white toothed whale of Arctic coastal waters, related to the narwhal. [Delphinapterus leucas.]
2. a very large sturgeon occurring in the inland seas and rivers of central Eurasia, from which caviar is obtained. [Huso huso.]