a state of rest or balance due to the equal action of opposing forces.
2.
equal balance between any powers, influences, etc.; equality of effect.
3.
mental or emotional balance; equanimity: The pressures of the situation caused her to lose her equilibrium.
4.
Chemistry . the condition existing when a chemical reaction and its reverse reaction proceed at equal rates. "
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"the condition of a system in which all competing influences are balanced, in a wide variety of contexts"
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List of types of equilibrium