| Noun | 1. | order Sirenia - an animal order including: manatees; dugongs; Steller's sea cowanimal order - the order of animals Eutheria, subclass Eutheria - all mammals except monotremes and marsupials sea cow, sirenian, sirenian mammal - any of two families of large herbivorous aquatic mammals with paddle-shaped tails and flipper-like forelimbs and no hind limbs family Trichechidae, Trichechidae - comprising only the manatees Dugongidae, family Dugongidae - a family of mammals of order Sirenia including dugongs and Steller's sea cow |