hanky panky vs skullduggery

hanky panky and skullduggery both are nouns.

Word	Noun	Adjective	Verb	Adverb
hanky panky	Yes	No	No	No
skullduggery	Yes	No	No	No

As nouns, hanky panky and skullduggery are synonyms defined as:

hanky panky and skullduggery: verbal misrepresentation intended to take advantage of you in some way

Other synonyms of hanky panky include hocus-pocus, jiggery-pokery, skulduggery, slickness, trickery.

hanky panky (noun)	skullduggery (noun)
verbal misrepresentation intended to take advantage of you in some way	verbal misrepresentation intended to take advantage of you in some way