sweet Fanny Adams vs dirty word

sweet Fanny Adams and dirty word both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweet Fanny Adams	Yes	No	No	No
dirty word	Yes	No	No	No

sweet Fanny Adams (noun)	dirty word (noun)
little or nothing at all	an offensive or indecent word or phrase
	a word that is considered to be unmentionable