geographic region vs Tidewater

geographic region and Tidewater both are nouns.

Word	Noun	Adjective	Verb	Adverb
geographic region	Yes	No	No	No
Tidewater	Yes	No	No	No

geographic region (noun)	Tidewater (noun)
a demarcated area of the Earth	the coastal plain of the South: eastern parts of Virginia and North Carolina and South Carolina and Georgia