apt or liable to vary or change; changeable: variable weather;variable moods.
capable of being varied or changed; alterable: a variable time limit for completion of a book.
inconstant; fickle: a variable lover.
having much variation or diversity.
Biology. deviating from the usual type, as a species or a specific character.
Astronomy. (of a star) changing in brightness.
Meteorology. (of wind) tending to change in direction.
Mathematics. having the nature or characteristics of a variable.
noun
something that may or does vary or change; a variable feature or factor.
Mathematics, Computers.
a quantity or function that may assume any given value or set of values.
a symbol that represents this.
Logic. (in the functional calculus) a symbol for an unspecified member of a class of things or statements.Compare bound variable, free variable.
Astronomy. variable star.
Meteorology.
a shifting wind, especially as distinguished from a trade wind.
variables,doldrums (def. 2a).
Origin of variable
First recorded in 1350–1400; late Middle English, from Latin variābilis, equivalent to vari(us) “speckled, variegate, diverse” + -ābilis adjective suffix; see various, -able
A mathematical quantity capable of assuming any of a set of values, such as x in the expression 3x + 2.
A factor or condition that is subject to change, especially one that is allowed to change in a scientific experiment to test a hypothesis. See more at control.