Megatheriidae vs mammal family

Megatheriidae and mammal family both are nouns.

Word	Noun	Adjective	Verb	Adverb
Megatheriidae	Yes	No	No	No
mammal family	Yes	No	No	No

As nouns, mammal family is a hypernym of Megatheriidae; that is, mammal family is a word with a broader meaning than Megatheriidae:

Megatheriidae (noun)	mammal family (noun)
extinct ground sloths	a family of mammals