Valeyard
From Jenny Everywhere Wiki
When departing from Gallifrey in the one universe very similar to the Third Universe, a decisive First Doctor thought to himself that he would “not spend another day on this planet of vampires and valeyards”. (PROSE: How To Steal Timeships & To Influence Time Lords)
Behind the scenes
Most famously the title taken on by a future, evil version of the Doctor, the title “valeyard” was established to originally have been coined on Gallifrey as a word for a “learned court prosecutor”. The line in PROSE: How To Steal Timeships & To Influence Time Lords is a direct reference to a similar line uttered by the “prime” First Doctor shortly before leaving Gallifrey in a flashback included in the novel Cold Fusion.