Instantiating a template is the process in which
- the compiler uses the argument(s) of the call to deduce the template parameter(s),
- the compiler uses the deduced template parameter(s) to create a specific version (new "instance") of the template using the actual argument(s) in place of the corresponding template parameter(s).
Instantiation of a template is the compiler-generated specific version (with the actual argument) of the template.