St. Francis River vs Saint Francis

St. Francis River and Saint Francis both are nouns.

Word	Noun	Adjective	Verb	Adverb
St. Francis River	Yes	No	No	No
Saint Francis	Yes	No	No	No

As nouns, St. Francis River and Saint Francis are synonyms defined as:

St. Francis River and Saint Francis: a tributary of the Mississippi River that rises in Missouri and flows southeastward through Arkansas

Other synonyms of St. Francis River include Saint Francis River, St. Francis.

St. Francis River (noun)	Saint Francis (noun)
a tributary of the Mississippi River that rises in Missouri and flows southeastward through Arkansas	a tributary of the Mississippi River that rises in Missouri and flows southeastward through Arkansas
	(Roman Catholic Church) an Italian and the Roman Catholic monk who founded the Franciscan order of friars (1181-1226)