Variable

1. (a.) Having the capacity of varying or changing; capable of alternation in any manner; changeable; as, variable winds or seasons; a variable quantity.
2. (a.) Liable to vary; too susceptible of change; mutable; fickle; unsteady; inconstant; as, the affections of men are variable; passions are variable.
3. (n.) That which is variable; that which varies, or is subject to change.
4. (n.) A quantity which may increase or decrease; a quantity which admits of an infinite number of values in the same expression; a variable quantity; as, in the equation x2 - y2 = R2, x and y are variables.
5. (n.) A shifting wind, or one that varies in force.
6. (n.) Those parts of the sea where a steady wind is not expected, especially the parts between the trade-wind belts.