fossorial mammal vs mammal

fossorial mammal and mammal both are nouns.

Word	Noun	Adjective	Verb	Adverb
fossorial mammal	Yes	No	No	No
mammal	Yes	No	No	No

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

fossorial mammal: a burrowing mammal having limbs adapted for digging
mammal: any warm-blooded vertebrate having the skin more or less covered with hair; young are born alive except for the small subclass of monotremes and nourished with milk

Other hypernyms of fossorial mammal include mammalian.

fossorial mammal (noun)	mammal (noun)
a burrowing mammal having limbs adapted for digging	any warm-blooded vertebrate having the skin more or less covered with hair; young are born alive except for the small subclass of monotremes and nourished with milk