sirenian mammal vs sea cow

sirenian mammal and sea cow both are nouns.

Word	Noun	Adjective	Verb	Adverb
sirenian mammal	Yes	No	No	No
sea cow	Yes	No	No	No

As nouns, sirenian mammal and sea cow are synonyms defined as:

sirenian mammal and sea cow: any of two families of large herbivorous aquatic mammals with paddle-shaped tails and flipper-like forelimbs and no hind limbs

Other synonyms of sirenian mammal include sirenian.

sirenian mammal (noun)	sea cow (noun)
any of two families of large herbivorous aquatic mammals with paddle-shaped tails and flipper-like forelimbs and no hind limbs	any of two families of large herbivorous aquatic mammals with paddle-shaped tails and flipper-like forelimbs and no hind limbs