Pronunciation: (bu-lOO'gu), [key]
1. Also called hausen. a white sturgeon, Huso huso, of the Black and Caspian seas, valued as a source of caviar and isinglass.
2. Also called white whale. a cetacean, Delphinapterus leucas, of northern seas, that has a rounded head and is white when adult.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.