Economic Definition of stable equilibrium. Defined.
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Term stable equilibrium Definition: An equilibrium that is restored if disrupted by an external force. This should be contrasted with unstable equilibrium. Most equilibria studied in economics are of the stable variety. The most common example is market equilibrium. Should the existing market equilibrium be disrupted by a change in one of the demand or supply determinants, the resulting shortage or surplus causes the price to change, which causes changes in quantity demanded and quantity supplied needed to restore equilibrium. The new equilibrium may by, and probably is, at a different equilibrium price and quantity, but it is equilibrium, and it will remain there until disrupted by an external force.