biscuit vs quick bread

biscuit and quick bread both are nouns.

Word	Noun	Adjective	Verb	Adverb
biscuit	Yes	No	No	No
quick bread	Yes	No	No	No

As nouns, quick bread is a hypernym of biscuit; that is, quick bread is a word with a broader meaning than biscuit:

biscuit: small round bread leavened with baking-powder or soda
quick bread: breads made with a leavening agent that permits immediate baking

biscuit (noun)	quick bread (noun)
small round bread leavened with baking-powder or soda	breads made with a leavening agent that permits immediate baking
any of various small flat sweet cakes