scrunch vs scrunch up

scrunch is a noun but scrunch up is not a noun.

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

As verbs, scrunch and scrunch up are synonyms defined as:

scrunch and scrunch up: make wrinkles or creases on a smooth surface; make a pressed, folded or wrinkled line in; `crisp' is archaic

Other synonyms of scrunch include crease, crinkle, crisp, ruckle, wrinkle.

As verbs, scrunch and scrunch up are synonyms defined as:

Other synonyms of scrunch include crouch, hunker, hunker down, squat.

scrunch (noun)	scrunch up (noun)
a crunching noise

scrunch (verb)	scrunch up (verb)
make wrinkles or creases on a smooth surface; make a pressed, folded or wrinkled line in; `crisp' is archaic	make wrinkles or creases on a smooth surface; make a pressed, folded or wrinkled line in; `crisp' is archaic
sit on one's heels	sit on one's heels
make a noise typical of an engine lacking lubricants