Dnieper River vs Dnieper

Dnieper River and Dnieper both are nouns.

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

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

Dnieper River and Dnieper: a river that rises in Russia near Smolensk and flowing south through Belarus and Ukraine to empty into the Black Sea

Dnieper River (noun)	Dnieper (noun)
a river that rises in Russia near Smolensk and flowing south through Belarus and Ukraine to empty into the Black Sea	a river that rises in Russia near Smolensk and flowing south through Belarus and Ukraine to empty into the Black Sea