Brf is right, it is a title, I am just being a little confused as I didn't know what you meant really, however..
There are different alternatives you have if you want a user to have a special title.
1. You can make a group and then set the group to have the title "x" as default, notice that you will need to make a title before you can do this.
2. Use postcount titles (You can do this in the title manager page)