Colorado vs Arkansas River

Colorado and Arkansas River both are nouns.

Word	Noun	Adjective	Verb	Adverb
Colorado	Yes	No	No	No
Arkansas River	Yes	No	No	No

Colorado (noun)	Arkansas River (noun)
a state in west central United States in the Rocky Mountains	a river that rises in the Rocky Mountains in Colorado and flows southeast through Kansas and Oklahoma and through Arkansas to become a tributary of the Mississippi River
an important river in the southwestern United States; rises in the Rocky Mountains of northern Colorado and flows southwest through Utah into Arizona (where it flows through the Grand Canyon) and then southward through the southern tip of Nevada, then forming the border between California and Arizona and finally into Mexico where it empties into the Gulf of California; the main source of water in the southwestern United States
a river in Texas; flows southeast into the Gulf of Mexico