Kithriarch
From Tardis Wiki, the free Doctor Who reference
Kithriarch was a title in Time Lord society given to the head of each of the families of the Great Houses (PROSE: Lungbarrow). The Kithriarch was not the same as the Housekeeper, who was responsible for the well-being of the House itself. The Kithriarch was responsible for the social well-being of each family member. (PROSE: Lungbarrow)
The position of Kithriarch was retained through regenerations. On the Kithriarch's final death, he would name his successor. (PROSE: Lungbarrow)