Araguaya River vs Araguaia

Araguaya River and Araguaia both are nouns.

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

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

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

Other synonyms of Araguaya River include Araguaia River, Araguaya.

Araguaya River (noun)	Araguaia (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