clam vs bank bill

clam and bank bill both are nouns.

Word	Noun	Adjective	Verb	Adverb
clam	Yes	No	Yes	No
bank bill	Yes	No	No	No

As nouns, bank bill is a hypernym of clam; that is, bank bill is a word with a broader meaning than clam:

clam (noun)	bank bill (noun)
burrowing marine mollusk living on sand or mud; the shell closes with viselike firmness	a piece of paper money (especially one issued by a central bank)
flesh of either hard-shell or soft-shell clams
a piece of paper money worth one dollar

clam (verb)	bank bill (verb)
gather clams, by digging in the sand by the ocean