operative

(ŏpˈər-ə-tĭv, -ə-rāˌtĭv, ŏpˈrə-)

1. Being in effect; having force; operating: “Two major tendencies are operative in the American political system” (Heinz Eulau).
2. Functioning effectively; efficient.
3. Engaged in or concerned with physical or mechanical activity.
4. Of, relating to, or resulting from a surgical operation.
5. Significant; most important; key: The operative word is “low-fat.”

1. A skilled worker, especially in industry.
2. a. A secret agent; a spy.
   b. A private investigator.
3. One who works for a political organization, often wielding influence out of public view.

Related Forms:

• opˈer·a·tive·ly adverb