River Ouse vs Ouse

River Ouse and Ouse both are nouns.

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

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

River Ouse and Ouse: a river in northeastern England that flows generally southeastward to join the Trent River and form the Humber

Other synonyms of River Ouse include Ouse River.

River Ouse (noun)	Ouse (noun)
a river in northeastern England that flows generally southeastward to join the Trent River and form the Humber	a river in northeastern England that flows generally southeastward to join the Trent River and form the Humber