Araguaia River vs Araguaya River

Araguaia River and Araguaya River both are nouns.

Word	Noun	Adjective	Verb	Adverb
Araguaia River	Yes	No	No	No
Araguaya River	Yes	No	No	No

As nouns, Araguaia River and Araguaya River are synonyms defined as:

Araguaia River and Araguaya River: a river in central Brazil that flows generally northward (with many falls) to join the Tocantins River

Other synonyms of Araguaia River include Araguaia, Araguaya.

Araguaia River (noun)	Araguaya River (noun)
a river in central Brazil that flows generally northward (with many falls) to join the Tocantins River	a river in central Brazil that flows generally northward (with many falls) to join the Tocantins River