Something that is variable.
Something whose value may be dictated or discovered.
There are several variables to consider here.
A quantity that may assume any one of a set of values.
A symbol representing a variable.
A named memory location in which a program can store intermediate results and from which it can read them.
A variable star.
A shifting wind, or one that varies in force.
(in the plural) Those parts of the sea where a steady wind is not expected, especially the parts between the trade-wind belts.