quadroon vs mixed-blood

quadroon and mixed-blood both are nouns.

Word	Noun	Adjective	Verb	Adverb
quadroon	Yes	No	No	No
mixed-blood	Yes	No	No	No

As nouns, mixed-blood is a hypernym of quadroon; that is, mixed-blood is a word with a broader meaning than quadroon:

quadroon: an offspring of a mulatto and a white parent; a person who is one-quarter black
mixed-blood: a person whose ancestors belonged to two or more racial groups

quadroon (noun)	mixed-blood (noun)
an offspring of a mulatto and a white parent; a person who is one-quarter black	a person whose ancestors belonged to two or more racial groups