actual argument
In a function call, the value being passed by the calling routine as an
argument to the programmer-defined function. This value must be of a compatible data
type with the corresponding formal argument in the function definition. There
are two methods for an actual argument to be passed to a function:
pass-by-reference and pass-by-value.
See also argument, calling routine, data type conversion, formal argument, function call, pass-by-reference, pass-by-value, programmer-defined function.