From HomoExcelsior

1. Likely to change or vary; subject to variation; changeable. 2. Inconstant; fickle. 3. Tending to deviate, as from a normal or recognized type; aberrant. 4. Having no fixed quantitative value. 5. Something that varies or is prone to variation. 6. A variable star. 7. A quantity capable of assuming any of a set of values. 8.  are variables.

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