Method Signature

Definitions

The combination of a method's name, its parameter types and order, and (in some languages) its return type, which together uniquely identify the method and enable overloading and type checking.
In plain English: The name of a function plus the types and order of its inputs, which together define how you're allowed to call it.
Example: "The compiler flagged the call because no overload matched the method signature — you're passing a string where it expects an int."