Tocantins River vs Tocantins

Tocantins River and Tocantins both are nouns.

Word	Noun	Adjective	Verb	Adverb
Tocantins River	Yes	No	No	No
Tocantins	Yes	No	No	No

As nouns, Tocantins River and Tocantins are synonyms defined as:

Tocantins River and Tocantins: a river in eastern Brazil that flows generally north to the Para River

Tocantins River (noun)	Tocantins (noun)
a river in eastern Brazil that flows generally north to the Para River	a river in eastern Brazil that flows generally north to the Para River