push back vs rollback

push back and rollback both are nouns.

Word	Noun	Adjective	Verb	Adverb
push back	Yes	No	Yes	No
rollback	Yes	No	No	No

As nouns, push back and rollback are synonyms defined as:

push back (noun)	rollback (noun)
the act of forcing the enemy to withdraw	the act of forcing the enemy to withdraw
	reducing prices back to some earlier level

push back (verb)	rollback (verb)
cause to move back by force or influence