Sirenia

plural noun

Si·​re·​nia

sīˈrēnēə

: an order of large aquatic herbivorous mammals including the manatee, dugong, Steller's sea cow, and several fossil forms that have the tail horizontally flattened and expanded into a broad rounded or bilobed fin, the hind limbs rudimentary or wanting and the front ones paddle-shaped, and jaws with horny plates on the front part and usually numerous flat-crowned molar teeth

Word History

Etymology

New Latin, from Latin siren + New Latin -ia

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