A tutor was one who privately taught a single student or a very small group.
Aristotle was tutor to Alexander the Great. (AUDIO: Mask of Tragedy) Bengel was a senior tutor. (AUDIO: White Ghosts) Borusa was tutor to the First Doctor. (TV: The Deadly Assassin) The First Doctor was tutor to Jane Grey. (PROSE: The Nine-Day Queen) The Twelfth Doctor was tutor to Bill Potts at St Luke's University in the 2010s. (TV: The Pilot) Marion Fleming was the personal tutor to Alex Campbell in the 2190s. (AUDIO: An Earthly Child) The Bernard Helmann was a philosophy tutor at the University of Oxford. (PROSE: Come Friendly Bombs...) Magrantine was a Kaled tutor. (AUDIO: Innocence) Sepulchra was tutor to Caleera at the Time Lord Academy. (AUDIO: Scenes From Her Life) Edward Stott was a university principal who acted as tutor to an expedition seeking the Artifact around 2515. (PROSE: Parasite)