[noun] [U] [slightly formal] - a state of balanceThe disease destroys much of the inner-ear, disturbing the animal's equilibrium.The resignation of the president upset the country's economic equilibrium.(slightly formal) Equilibrium can also be a state of mental calmness.Yoga is said to restore one's inner (= mental) equilibrium.
EQUILIBRIUM
Meaning of EQUILIBRIUM in English
Cambridge English vocab. Кембриджский английский словарь. 2012