What does "countervail" mean?

Countervail: To act against with equal force, power, or effect; to thwart or overcome by such action; to furnish an equivalent to or for; to counterbalance; to compensate. Upon balancing the account, the profit at last will hardly countervail the inconveniences that go allong with it. L'Estrange.

Additional senses

  1. 2.Power or value sufficient to obviate any effect; equal weight, strength, or value; equivalent; compensation; requital. [Obs.] Surely, the present pleasure of a sinful act is a poor countervail for the bitterness of the review. South.

Sources