gnawer vs eutherian

gnawer and eutherian both are nouns.

Word	Noun	Adjective	Verb	Adverb
gnawer	Yes	No	No	No
eutherian	Yes	Yes	No	No

As nouns, eutherian is a hypernym of gnawer; that is, eutherian is a word with a broader meaning than gnawer:

gnawer: relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing
eutherian: mammals having a placenta; all mammals except monotremes and marsupials

Other hypernyms of gnawer include eutherian mammal, placental, placental mammal.

gnawer (noun)	eutherian (noun)
relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing	mammals having a placenta; all mammals except monotremes and marsupials

gnawer (adjective)	eutherian (adjective)
	of or relating to or belonging to the subclass Eutheria