slave state vs American state

slave state and American state both are nouns.

Word	Noun	Adjective	Verb	Adverb
slave state	Yes	No	No	No
American state	Yes	No	No	No

As nouns, American state is a hypernym of slave state; that is, American state is a word with a broader meaning than slave state:

slave state: any of the southern states in which slavery was legal prior to the American Civil War
American state: one of the 50 states of the United States

slave state (noun)	American state (noun)
any of the southern states in which slavery was legal prior to the American Civil War	one of the 50 states of the United States