bank bill vs banker's bill

bank bill and banker's bill both are nouns.

Word	Noun	Adjective	Verb	Adverb
bank bill	Yes	No	No	No
banker's bill	Yes	No	No	No

As nouns, bank bill and banker's bill are synonyms defined as:

bank bill and banker's bill: a piece of paper money (especially one issued by a central bank)

Other synonyms of bank bill include bank note, banknote, bill, Federal Reserve note, government note, greenback, note.

bank bill (noun)	banker's bill (noun)
a piece of paper money (especially one issued by a central bank)	a piece of paper money (especially one issued by a central bank)