If you describe a word as the operative word, you want to draw attention to it because you think it is important or exactly true in a particular situation. As long as the operative word is `greed', you can't count on people keeping the costs down
being in force or having or exerting force; "operative regulations"; "the major tendencies operative in the American political system" effective; producing a desired effect; "the operative word" of or relating to a surgical operation; "operative surgery
A system or service that is operative is working or having an effect. The commercial telephone service was no longer operative