billy goat vs caprine animal

billy goat and caprine animal both are nouns.

Word	Noun	Adjective	Verb	Adverb
billy goat	Yes	No	No	No
caprine animal	Yes	No	No	No

As nouns, caprine animal is a hypernym of billy goat; that is, caprine animal is a word with a broader meaning than billy goat:

billy goat: male goat
caprine animal: any of numerous agile ruminants related to sheep but having a beard and straight horns

Other hypernyms of billy goat include goat.

billy goat (noun)	caprine animal (noun)
male goat	any of numerous agile ruminants related to sheep but having a beard and straight horns