banker's bill vs paper currency

banker's bill and paper currency both are nouns.

Word	Noun	Adjective	Verb	Adverb
banker's bill	Yes	No	No	No
paper currency	Yes	No	No	No

As nouns, paper currency is a hypernym of banker's bill; that is, paper currency is a word with a broader meaning than banker's bill:

banker's bill: a piece of paper money (especially one issued by a central bank)
paper currency: currency issued by a government or central bank and consisting of printed paper that can circulate as a substitute for specie

Other hypernyms of banker's bill include folding money, paper money.

banker's bill (noun)	paper currency (noun)
a piece of paper money (especially one issued by a central bank)	currency issued by a government or central bank and consisting of printed paper that can circulate as a substitute for specie