beluga

noun2

1. •
   A whale, Delphinapterus leucas, found in the Arctic Ocean.

   • Each summer some 1,500 belugas gather in Cunningham Inlet, drawn in part by the clean sand-and-gravel bottom in the shallows. — 1989
2. •
   A fish, Huso huso, that is a source of caviar, which is found in the Black Sea and the Caspian Sea.