Noun
a genus of the family Dugongidae comprising only Steller's sea cow
Source: WordNetHydrodamalis gigas, Steller's sea cow, could reach lengths of 8 m. citation The three manatee species (family Trichechidae) and the dugong (family Dugongidae) are endangered species. Source: Internet
Hunting of sea otters, for example, is thought to have led indirectly to the extinction of the Steller's sea cow (Hydrodamalis gigas). Source: Internet