Parameter
Noun · Development
Definitions
A named variable in a function or method declaration that acts as a placeholder for data passed in at call time. Parameters define what a function expects; arguments are the actual values supplied. Confused with 'argument' by approximately everyone.
In plain English: A slot in a function definition that gets filled with a real value when you actually call the function — like blanks in a form waiting to be filled in.
Example: "The function takes three parameters: name, age, and an optional callback."