yearling vs eutherian

yearling and eutherian both are nouns.

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

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

yearling: an animal in its second year
eutherian: mammals having a placenta; all mammals except monotremes and marsupials

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

yearling (noun)	eutherian (noun)
an animal in its second year	mammals having a placenta; all mammals except monotremes and marsupials
a racehorse considered one year old until the second Jan. 1 following its birth
a young child who is just beginning to walk

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