effective vs operative

effective is not a noun while operative is a noun.

Word	Noun	Adjective	Verb	Adverb
effective	No	Yes	No	No
operative	Yes	Yes	No	No

effective (noun)	operative (noun)
	someone who can be employed as a detective to collect information and assist in criminal investigations
	a person secretly employed in espionage for a government

effective (adjective)	operative (adjective)
producing or capable of producing an intended result or having a striking effect	being in force or having or exerting force
existing in fact; not theoretical; real	relating to or requiring or amenable to treatment by surgery especially as opposed to medicine
able to accomplish a purpose; functioning effectively	(of e.g. a machine) performing or capable of performing
works well as a means or remedy	effective; producing a desired effect
ready for service
exerting force or influence