A force or element that brings about equilibrium; a balancing force that exactly counteracts other forces.
From Latin 'equilibrium' (equal balance) with the suffix '-ant' (agent noun indicating something that causes an action). It's a technical term from physics and mechanics.
If you have multiple forces pushing on an object, the equilibrant is the single force that would perfectly cancel them all out—it's the concept behind tug-of-war, where one perfectly positioned pull equals all the others combined.
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