Key holder is someone who is given a key and the authority to have access to the back door, opening and closing of the store etc. On occasion you would be a shift supervisor.
Yes, it's basically a technical term that seems to make the employee feel like they have a position that is far more glorified than it is.
Key Holder is a little bit of a higher position, It gives you the advantage to open and lock the doors which gives you open and close shifts guaranteed over other associates
Privileges of opening/closing the store. Managing daily schedule and performing a bigger variety of tasks as a pose to just an associate.
Basically you are a shift leader. You get a key to open and close the store.