operation vs operative

operation and operative both are nouns.

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

operation (noun)	operative (noun)
a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body	someone who can be employed as a detective to collect information and assist in criminal investigations
(mathematics) calculation by mathematical methods	a person secretly employed in espionage for a government
activity by a military or naval force (as a maneuver or campaign)
a planned activity involving many people performing various actions
a process or series of acts especially of a practical or mechanical nature involved in a particular form of work
a business especially one run on a large scale
the activity of operating something (a machine or business etc.)
(psychology) the performance of some composite cognitive activity; an operation that affects mental contents
(computer science) data processing in which the result is completely specified by a rule (especially the processing that results from a single instruction)
process or manner of functioning or operating
the state of being in effect or being operative

operation (adjective)	operative (adjective)
	being in force or having or exerting force
	relating to or requiring or amenable to treatment by surgery especially as opposed to medicine
	(of e.g. a machine) performing or capable of performing
	effective; producing a desired effect