fold up vs ruffle

fold up is not a noun while ruffle is a noun.

Word	Noun	Adjective	Verb	Adverb
fold up	No	No	Yes	No
ruffle	Yes	No	Yes	No

As verbs, ruffle is a hyponym of fold up; that is, ruffle is a word with a more specific, narrower meaning than fold up:

fold up (noun)	ruffle (noun)
	a noisy fight
	a high tight collar
	a strip of pleated material used as a decoration or a trim

fold up (verb)	ruffle (verb)
become folded or folded up	pleat or gather into a ruffle
bend or lay so that one part covers the other	erect or fluff up
	disturb the smoothness of
	twitch or flutter
	mix so as to make a random order or arrangement
	trouble or vex
	discompose
	stir up (water) so as to form ripples
	to walk with a lofty proud gait, often in an attempt to impress others