Bluegrass vs Bluegrass Region

Bluegrass and Bluegrass Region both are nouns.

Word	Noun	Adjective	Verb	Adverb
Bluegrass	Yes	No	No	No
Bluegrass Region	Yes	No	No	No

As nouns, Bluegrass and Bluegrass Region are synonyms defined as:

Bluegrass and Bluegrass Region: an area in central Kentucky noted for its bluegrass and thoroughbred horses

Other synonyms of Bluegrass include Bluegrass Country.

Bluegrass (noun)	Bluegrass Region (noun)
an area in central Kentucky noted for its bluegrass and thoroughbred horses	an area in central Kentucky noted for its bluegrass and thoroughbred horses