Deep South vs Mississippi

Deep South and Mississippi both are nouns.

Word	Noun	Adjective	Verb	Adverb
Deep South	Yes	No	No	No
Mississippi	Yes	No	No	No

Deep South (noun)	Mississippi (noun)
the southeastern region of the United States: South Carolina and Georgia and Alabama and Mississippi and Louisiana; prior to the American Civil War all these states produced cotton and permitted slavery	a state in the Deep South on the gulf of Mexico; one of the Confederate States during the American Civil War
	a major North American river and the chief river of the United States; rises in northern Minnesota and flows southward into the Gulf of Mexico