digitigrade vs placental mammal

digitigrade and placental mammal both are nouns.

Word	Noun	Adjective	Verb	Adverb
digitigrade	Yes	Yes	No	No
placental mammal	Yes	No	No	No

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

digitigrade: an animal that walks so that only the toes touch the ground as e.g. dogs and cats and horses
placental mammal: mammals having a placenta; all mammals except monotremes and marsupials

Other hypernyms of digitigrade include eutherian, eutherian mammal, placental.

digitigrade (noun)	placental mammal (noun)
an animal that walks so that only the toes touch the ground as e.g. dogs and cats and horses	mammals having a placenta; all mammals except monotremes and marsupials

digitigrade (adjective)	placental mammal (adjective)
(of mammals) walking on the toes with the posterior part of the foot raised (as cats, dogs, and horses do)