goat vs Capra hircus

goat and Capra hircus both are nouns.

Word	Noun	Adjective	Verb	Adverb
goat	Yes	No	No	No
Capra hircus	Yes	No	No	No

As nouns, Capra hircus is a hyponym of goat; that is, Capra hircus is a word with a more specific, narrower meaning than goat:

goat: any of numerous agile ruminants related to sheep but having a beard and straight horns
Capra hircus: any of various breeds of goat raised for milk or meat or wool

Other hyponyms of goat include kid, billy, billy goat, he-goat, nanny-goat, nanny, she-goat, domestic goat, wild goat.

goat (noun)	Capra hircus (noun)
any of numerous agile ruminants related to sheep but having a beard and straight horns	any of various breeds of goat raised for milk or meat or wool
a victim of ridicule or pranks