sīˈrēnēə noun plural
Usage: capitalized
Etymology: New Latin, from Latin siren + New Latin -ia
: 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