v. t. [ imp. & p. p. Countervailed p. pr. & vb. n. Countervailing. ] [ OF. contrevaloir; contre (L. contra) + valoir to avail, fr. L. valere to be strong, avail. See Vallant. ] 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. [ 1913 Webster ]

Upon balancing the account, the profit at last will hardly countervail the inconveniences that go allong with it. L'Estrange. [ 1913 Webster ]

n. Power or value sufficient to obviate any effect; equal weight, strength, or value; equivalent; compensation; requital. [ Obs. ] [ 1913 Webster ]

Surely, the present pleasure of a sinful act is a poor countervail for the bitterness of the review. South. [ 1913 Webster ]