packhorse vs pack animal

packhorse and pack animal both are nouns.

Word	Noun	Adjective	Verb	Adverb
packhorse	Yes	No	No	No
pack animal	Yes	No	No	No

As nouns, pack animal is a hypernym of packhorse; that is, pack animal is a word with a broader meaning than packhorse:

packhorse: a workhorse used as a pack animal
pack animal: an animal (such as a mule or burro or horse) used to carry loads

Other hypernyms of packhorse include sumpter, workhorse.

packhorse (noun)	pack animal (noun)
a workhorse used as a pack animal	an animal (such as a mule or burro or horse) used to carry loads