Title of the central character in a series of stories by
Diana Wynne Jones. Chrestomanci (Or the Chrestomancis, as the word actually refers to a position held by multiple people) is a powerful enchanter with nine lives. He lives in a world, one of many parallel worlds, wherein magic is common, and he works for the British Government to prevent the misuse of magic.
He appears in the stories "Charmed Life", "Witch Week", "The Magicians of Caprona", and "The Lives of Christopher Chant", the four of which are collected in The Chrestomanci Quartet".