noun
1. someone who can be employed as a detective to collect information
Synonym: private detectivePIprivate eyeprivate investigatorshamussherlock
2. a person secretly employed in espionage for a government
Synonym: secret agentintelligence officerintelligence agent
adj
1. being in force or having or exerting force
e.g. operative regulations
the major tendencies operative in the American political system
2. (of e.g. a machine) performing or capable of performing
e.g. in running (or working) order
a functional set of brakes
Synonym: running(a)functionalworking(a)
3. relating to or requiring or amenable to treatment by surgery especially as opposed to medicine
e.g. a surgical appendix
a surgical procedure
operative dentistry
Synonym: surgical
4. effective
producing a desired effect
e.g. the operative word