/ ˌiːkwɪˈlɪbriəm; NAmE ; ˌek-/ noun [ U , sing. ]
1.
a state of balance, especially between opposing forces or influences :
The point at which the solid and the liquid are in equilibrium is called the freezing point.
Any disturbance to the body's state of equilibrium can produce stress.
We have achieved an equilibrium in the economy.
2.
a calm state of mind and a balance of emotions :
He sat down to try and recover his equilibrium.
••
WORD ORIGIN
early 17th cent. (in the sense well-balanced state of mind ): from Latin aequilibrium , from aequi- equal+ libra balance.