Operative

operative
1. Having the power of acting; hence, exerting force, physical or moral; active in the production of effects; as, an operative motive. It holds in all operative principles. (south)
2. Producing the appropriate or designed effect; efficacious; as, an operative dose, rule, or penalty.
3. (Science: surgery) Based upon, or consisting of, an operation or operations; as, operative surgery.
Origin: Cf.L. Operativus, F. Operatif.