Dakota language vs Siouan

Dakota language and Siouan both are nouns.

Word	Noun	Adjective	Verb	Adverb
Dakota language	Yes	No	No	No
Siouan	Yes	Yes	No	No

As nouns, Siouan is a hypernym of Dakota language; that is, Siouan is a word with a broader meaning than Dakota language:

Other hypernyms of Dakota language include Siouan language.

Dakota language (noun)	Siouan (noun)
the Siouan language spoken by the Dakota	a family of North American Indian languages spoken by the Sioux
	a member of a group of North American Indian peoples who spoke a Siouan language and who ranged from Lake Michigan to the Rocky Mountains

Dakota language (adjective)	Siouan (adjective)
	of or relating to the Sioux people or their language and culture