rollback vs decrease

rollback and decrease both are nouns.

Word	Noun	Adjective	Verb	Adverb
rollback	Yes	No	No	No
decrease	Yes	No	Yes	No

As nouns, decrease is a hypernym of rollback; that is, decrease is a word with a broader meaning than rollback:

Other hypernyms of rollback include diminution, reduction, step-down.

rollback (noun)	decrease (noun)
the act of forcing the enemy to withdraw	the act of decreasing or reducing something
reducing prices back to some earlier level	the amount by which something decreases
	a change downward
	a process of becoming smaller or shorter

rollback (verb)	decrease (verb)
	decrease in size, extent, or range
	make become smaller