Webster's Revised Unabridged Dictionary · 1913

Equipoise

Equipoise , noun

[Equi- + poise.]

1.
Equality of weight or force; hence, equilibrium; a state in which the two ends or sides of a thing are balanced, and hence equal; state of being equally balanced; -- said of moral, political, or social interests or forces.
The means of preserving the equipoise and the tranquillity of the commonwealth. — Burke
Our little lives are kept in equipoise By opposite attractions and desires. — Longfellow
2.
Counterpoise.
The equipoise to the clergy being removed. — Buckle