Navajo vs Athabascan

Navajo and Athabascan both are nouns.

Word	Noun	Adjective	Verb	Adverb
Navajo	Yes	No	No	No
Athabascan	Yes	No	No	No

As nouns, Athabascan is a hypernym of Navajo; that is, Athabascan is a word with a broader meaning than Navajo:

Navajo: the Athapaskan language spoken by the Navaho
Athabascan: a group of Amerindian languages (the name coined by an American anthropologist, Edward Sapir)

Other hypernyms of Navajo include Athabaskan, Athapascan, Athapaskan, Athapaskan language.

As nouns, Athabascan is a hypernym of Navajo; that is, Athabascan is a word with a broader meaning than Navajo:

Navajo: a member of an Athapaskan people that migrated to Arizona and New Mexico and Utah
Athabascan: a member of any of the North American Indian groups speaking an Athapaskan language and living in the subarctic regions of western Canada and central Alaska

Other hypernyms of Navajo include Athabaskan, Athapascan, Athapaskan.

Navajo (noun)	Athabascan (noun)
the Athapaskan language spoken by the Navaho	a group of Amerindian languages (the name coined by an American anthropologist, Edward Sapir)
a member of an Athapaskan people that migrated to Arizona and New Mexico and Utah	a member of any of the North American Indian groups speaking an Athapaskan language and living in the subarctic regions of western Canada and central Alaska