the sturgeon (Huso huso) native to the Black Sea and Caspian Sea; -- also called hausen. It is valued for its roe, sold as caviar, and is also used for production of isinglass. See also sturgeon. [PJC]
the caviar obtained from the beluga{2}; -- also called beluga caviar. The caviar of the beluga is considered the finest sort, larger and of a taste superior to that obtained from other sturgeon. See also sturgeon and caviar. [PJC]