Synonyms for Equilibrium (same or very similar meaning)
WordNet sense 1 (equality of distribution):
balance, counterbalance, equipoise
WordNet sense 2 (a chemical reaction and its reverse proceed at equal rates):
chemical equilibrium
WordNet sense 3 (a sensory system located in structures of the inner ear that registers the orientation of the head):
labyrinthine sense, sense of balance, sense of equilibrium, vestibular sense
From the ODE community, based on WordNet
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