Second Time Lord

Second Time Lord was the title held by the second-highest-ranking Time Lord in Gallifrey's hierarchy, below the First Time Lord and above the Third Time Lord. At the time 's theft of information about the Doomsday Weapon, the Second Time Lord (PROSE: Doctor Who and the Doomsday Weapon) was Adelphi. (PROSE: The Legacy of Gallifrey)

Behind the scenes
Originally, the Time Lord Chancellor in The End of Time was to be credited as as "The Second".