Lena vs Lena River

Lena and Lena River both are nouns.

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

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

Lena and Lena River: a Russian river in Siberia; flows northward into the Laptev Sea

Lena (noun)	Lena River (noun)
a Russian river in Siberia; flows northward into the Laptev Sea	a Russian river in Siberia; flows northward into the Laptev Sea