countervail \kown-tur-VAYL\, transitive verb:
1. To act against with equal force, power, or effect; to counteract.
2. To compensate for; to offset; to furnish or serve as an equivalent to.
1. To exert force against an opposing, often bad, influence or power.
-- Alden Whitman, "Career Built on Style and Dash Ended with Invasion of Egypt", New York Times, January 15, 1977