not of prime or central importance; "nonessential to the integral meanings of poetry"- Pubs.MLA
(sometimes followed by `to') minor or casual or subordinate in significance or nature or occurring as a chance concomitant or consequence; "incidental expenses"; "the road will bring other incidental advantages"; "extra duties incidental to the job"; "labor problems incidental to a rapid expansion"; "confusion incidental to a quick change"
a symbol (like x or y) that is used in mathematical or logical expressions to represent a variable quantity
something that is likely to vary; something that is subject to variation; "the weather is one variable to be considered"
(used of a device) designed so that a property (as e.g. light) can be varied; "a variable capacitor"; "variable filters in front of the mercury xenon lights"
liable to or capable of change; "rainfall in the tropics is notoriously variable"; "variable winds"; "variable expenses"