geographical region vs Big Bend

geographical region and Big Bend both are nouns.

Word	Noun	Adjective	Verb	Adverb
geographical region	Yes	No	No	No
Big Bend	Yes	No	No	No

geographical region (noun)	Big Bend (noun)
a demarcated area of the Earth	a triangular area in southwestern Texas on the Mexican border; formed by a bend in the Rio Grande