Cimarron River vs Cimarron

Cimarron River and Cimarron both are nouns.

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

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

Cimarron River and Cimarron: a river that rises in northeastern New Mexico and flows eastward into Oklahoma where it becomes a tributary of the Arkansas River

Cimarron River (noun)	Cimarron (noun)
a river that rises in northeastern New Mexico and flows eastward into Oklahoma where it becomes a tributary of the Arkansas River	a river that rises in northeastern New Mexico and flows eastward into Oklahoma where it becomes a tributary of the Arkansas River