A cetacean, Delphinapterus leucas, found in the Arctic Ocean.
A fish found in the Caspian Sea and the Black Sea (Huso huso), that is a source of caviar.
A cetacean, Delphinapterus leucas, found in the Arctic Ocean.
An obsession; monomania.
A printing plate used to manufacture a particular sports card, that is then issued as a collectible itself.