rollback vs push back

rollback and push back both are nouns.

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

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

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

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