2. (Math.) 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 x^{2} - y^{2} = R^{2}, x and y are variables.
3. (Naut.)
(a) A shifting wind, or one that varies in force.
(b) pl. Those parts of the sea where a steady wind is not
expected, especially the parts between the trade-wind
belts.
{Independent variable} (Math.), that one of two or more
variables, connected with each other in any way whatever,
to which changes are supposed to be given at will. Thus,
in the equation x^{2} - y^{2} = R^{2}, if arbitrary
changes are supposed to be given to x, then x is the
independent variable, and y is called a function of x.
There may be two or more independent variables in an
equation or problem. Cf. {Dependent variable}, under
{Dependent}.
2. Liable to vary; too susceptible of change; mutable;
fickle; unsteady; inconstant; as, the affections of men
are variable; passions are variable.
Lest that thy love prove likewise variable. --Shak.
His heart, I know, how variable and vain! --Milton.
{Variable exhaust} (Steam Eng.), a blast pipe with an
adjustable opening.
{Variable quantity} (Math.), a variable.
{Variable stars} (Astron.), fixed stars which vary in their
brightness, usually in more or less uniform periods.