undoer vs undo

undoer is a noun but undo is not a noun.

Word	Noun	Adjective	Verb	Adverb
undoer	Yes	No	No	No
undo	No	No	Yes	No

undoer (noun)	undo (noun)
a person who destroys or ruins or lays waste to
a person who unfastens or unwraps or opens
a seducer who ruins a woman

undoer (verb)	undo (verb)
	cancel, annul, or reverse an action or its effect
	cause to become loose
	remove the outer cover or wrapping of
	deprive of certain characteristics
	cause the ruin or downfall of