COUNTERVAIL, v.t. counter and L., to avail or be strong. To act against with equal force, or power; to equal; to act with equivalent effect against any thing; to balance; to compensate.
The profit will hardly countervail the inconveniences.
Although the enemy could not countervail the kings damage. Esther 7.
COUNTERVAIL, n. Equal weight or strength; power or value sufficient to obviate any effect; equal weight or value; compensation; requital.