First Time Lord
From Tardis Wiki, the free Doctor Who reference
The First Time Lord was the leader of the Time Lord High Tribunal, alongside the Second Time Lord and Third Time Lord. (PROSE: Doctor Who and the Doomsday Weapon) While having been in one body during his encounter with the Second Doctor, (TV: The War Games, PROSE: Doctor Who and the Doomsday Weapon) he later was in another form during the Doomsday Weapon crisis. (PROSE: Doctor Who and the Doomsday Weapon)
Opening the possibility that this was a transferable title, Morbius, a former Lord President, claimed to be "a Time Lord of the First Rank" in his battle with the Fourth Doctor. (TV: The Brain of Morbius)