one dollar bill vs dollar bill

one dollar bill and dollar bill both are nouns.

Word	Noun	Adjective	Verb	Adverb
one dollar bill	Yes	No	No	No
dollar bill	Yes	No	No	No

As nouns, one dollar bill and dollar bill are synonyms defined as:

one dollar bill and dollar bill: a piece of paper money worth one dollar

Other synonyms of one dollar bill include buck, clam, dollar.

one dollar bill (noun)	dollar bill (noun)
a piece of paper money worth one dollar	a piece of paper money worth one dollar