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.

3. One who works for a political organization, often wielding influence out of public view.