a weight balancing another weight; an equal weight, power, or influence acting in opposition; counterpoise.

to act against or oppose with an equal weight, force, or influence; offset.

verb

amend , atone for , balance , cancel , compensate , correct , counteract , counterpoise , countervail , equalize , make up for , outweigh , rectify , redeem , set off , make up , offset , stabilize , steady , neutralize , check , equiponderate