An equilibrium concept for a game of strategy. A set of strategies (one for each player) constitutes a Nash equilibrium if no player has incentive to change their strategy given the strategies chosen by the other players.
The Nash equilibrium is the standard equilibrium concept in game theory. There are some games for which the Nash equilibrium has unusual properties and several ‘refinements’ of Nash equilibrium have been considered. None of these has seen widespread adoption.
|Reference: Oxford Press Dictonary of Economics, 5th edt.|