beagle vs hound dog

beagle and hound dog both are nouns.

Word	Noun	Adjective	Verb	Adverb
beagle	Yes	No	No	No
hound dog	Yes	No	No	No

As nouns, hound dog is a hypernym of beagle; that is, hound dog is a word with a broader meaning than beagle:

beagle: a small short-legged smooth-coated breed of hound
hound dog: any of several breeds of dog used for hunting typically having large drooping ears

Other hypernyms of beagle include hound.

beagle (noun)	hound dog (noun)
a small short-legged smooth-coated breed of hound	any of several breeds of dog used for hunting typically having large drooping ears