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n. See sea cow.

adj. Of or belonging to the order of sea cows.

n. Any of a group of aquatic, herbivorous mammals, of the order Sirenia, including the manatees and dugong.

n. Any species of Sirenia.

Pertaining to or characteristic of a siren.

Pertaining to the Sirenia, or having their characters.

n. A member of the Sirenia, as a manatee, dugong, or sea-cow.

n. any of two families of large herbivorous aquatic mammals with paddle-shaped tails and flipper-like forelimbs and no hind limbs

"‘The earliest known fully quadrupedal sirenian’, Nature, 413, 625–7."

aquatic mammal   

hydrodamalis gigas    dugong    manatee    Steller's sea cow    dugong dugon    trichechus manatus