What does "counterpoise" mean?

Counterpoise: To act against with equal power; to balance. So many freeholders of English will be able to beard and counterpoise the rest. Spenser.

Additional senses

  1. 2.A weight sufficient to balance another, as in the opposite scale of a balance; an equal weight. Fastening that to our exact balance, we put a metalline counterpoise into the opposite scale. Boyle.
  2. 3.An equal power or force acting in opposition; a force sufficient to balance another force. The second nobles are a counterpoise to the higher nobility, that they grow not too potent. Bacon.
  3. 4.The relation of two weights or forces which balance each other; equilibrum; equiponderance. The pendulous round eart, with balanced air, In counterpoise. Milton.

Sources