dirty word vs Fanny Adams

dirty word and Fanny Adams both are nouns.

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

dirty word (noun)	Fanny Adams (noun)
an offensive or indecent word or phrase	nautical term for tinned meat
a word that is considered to be unmentionable	little or nothing at all