An element, feature, or factor that is liable to vary or change. In the experiment, temperature was the main variable affecting the results.
A symbol, such as x or y, used in mathematical expressions to represent a quantity that can change. In the equation y = 2x + 3, both x and y are variables.
A quantity that during a calculation is assumed to vary or be capable of varying in value. The scientist adjusted the variable to see how it would impact the outcome of the simulation.