slave market vs marketplace

slave market and marketplace both are nouns.

Word	Noun	Adjective	Verb	Adverb
slave market	Yes	No	No	No
marketplace	Yes	No	No	No

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

slave market: a marketplace where slaves were auctioned off (especially in the southern United States before the American Civil War)
marketplace: an area in a town where a public mercantile establishment is set up

Other hypernyms of slave market include market, market place, mart.

slave market (noun)	marketplace (noun)
a marketplace where slaves were auctioned off (especially in the southern United States before the American Civil War)	the world of commercial activity where goods and services are bought and sold
	an area in a town where a public mercantile establishment is set up