The head of a diocese is called a Bishop, or if it is an important diocese, an Archbishop. Some diocese are headed by a Cardinal, but that is just the designation of a Bishop or Archbishop who also serves an elector of the new pope.
The region under a bishop's control is called a diocese.
I believe that is incardination to the new diocese and excardination from the old.
The Diocese of the Bishop of Rome's other name is the Holy See.
A bishop has a "diocese" or a "see".
Administrative area of a Bishop
The Diocese of Richmond and the Diocese of Arlington are led by Bishops who have not been ordained Cardinals. For a list of American Cardinals see link below. There are also links to the dioceses Web sites.
it is a bishop
The Diocese Tribunal.
There are 194 Catholic Diocese in the United States. See the related links for a wikipedia listing of all the provinces and diocese. http://en.wikipedia.org/wiki/List_of_the_Catholic_dioceses_of_the_United_States
The leader of a diocese is a Bishop.However if the territory becomes larger and he is now in charge of more dioceses with more responsibilities,then he is an Archbishop.
The First Roman Catholic diocese in the United States was the Archdiocese of Baltimore. The seat for the diocese is the Cathedral of Mary our Queen. The Archdiocese of Baltimore also contains the oldest Roman Catholic cathedral in the United States, the Basilica of the National Shrine of the Assumption of the Blessed Virgin Mary, also more commonly called the Baltimore Basilica.