What is not stable; not firm, fixed, or constant; subject to change or overthrow. -- Un*sta"ble*ness, n. Chaucer. Unstable equilibrium. See Stable equilibrium, under Stable called?

unstable — Not stable; not firm, fixed, or constant; subject to change or overthrow. -- Un*sta"ble*ness, n. Chaucer. Unstable equilibrium. See Stable equilibrium, under Stable. (Webster's 1913.)

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