scrunch up vs pucker

scrunch up is not a noun while pucker is a noun.

Word	Noun	Adjective	Verb	Adverb
scrunch up	No	No	Yes	No
pucker	Yes	No	Yes	No

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

scrunch up: make wrinkles or creases on a smooth surface; make a pressed, folded or wrinkled line in; `crisp' is archaic
pucker: to gather something into small wrinkles or folds

Other hyponyms of scrunch up include cockle, crumple, knit, rumple, ruck, ruck up.

scrunch up (noun)	pucker (noun)
	an irregular fold in an otherwise even surface (as in cloth)

scrunch up (verb)	pucker (verb)
make wrinkles or creases on a smooth surface; make a pressed, folded or wrinkled line in; `crisp' is archaic	to gather something into small wrinkles or folds
sit on one's heels	draw together into folds or puckers
	become wrinkled or drawn together