Aliases of the Master

Like the Doctor, the renegade Time Lord known as the Master used many aliases. However, while the Doctor used false names on a fairly ad hoc basis to avoid awkward questions, the Master usually adopted them in order to further whatever scheme he was embarked upon at the time.

Alias	When used	Story	Etymology
Thascalos !Professor Carl Thascalos	to give Jamie McCrimmon the Necronomicon, and to gain access to facilities of the Newton Institute	Time Mon !The Nameless City The Time Monster	Greek for master, pointed out by Jo Grant
Masters !Colonel Masters	to infiltrate Rex Farrel's plastics company	Terror !Terror of the Autons
Keller !Emil Keller	assumed identity of the creator of the Keller Machine	Mind !The Mind of Evil	Emil is derived from the Latin word aemulus, meaning rival, and Keller is derived from Old English cwellere, meaning executioner
Jurgens !Martin Jurgens	while posing as an Adjudicator	Colony !Colony in Space	Anagram of Master Gunnjir (gunnjir is the spear of Odin, head of the Norse pantheon)
Magister !Reverend Magister	to insinuate himself socially into the Devil's End community	Dæmon !The Dæmons	Latin for master
Frey	whilst in Sweden, 141	The Spear of Destiny	Old Norse for master
LeMaitre !Inspector LeMaitre	to infiltrate a village fete by pretending to be a police inspector from Scotland Yard	Inspector !Last of the Gaderene	French for the master
Dominus !Duke Dominus	to impersonate a 1930s Chicago gangster	Duke !The Duke of Dominoes	Dominus from the Latin for lord or master of the house
Estro	while posing as an adviser to Lord Haldoran in an effort to procure a Dalek matter transmuter	Legacy of the Daleks	Esperanto for master
Mwalimu	while hiding beneath Colonel Spindleton's manor house in 1979	Trail of the White Worm	Swahili for master in the sense of teacher
Interplanetary Police Inspector Efendi	while on Secus	The Evil One	Turkish for "Master"
Portreeve !The Portreeve	to trap the Fifth Doctor in Castrovalva	Castrovalva
Kalid	used to take control of the Xeraphin gestalt	Time-Flight	As Kalid, he affected the identity of a vaguely Arabian sorcerer. Kalid derives from the Indian Kalidasa meaning servant of Kali, an Indian goddess of time and change and usually depicted as being dark and violent.
Estram !Sir Gilles Estram	to avert the signing of the Magna Carta in 1215.	The King's Demons	Estram is a simple anagram.
Sheriff !The Sheriff	to gain access to the regenerative fountain near Eternity, California.	Town Called !A Town Called Eternity
Gospodar	to access the TITAN Array in order to destroy the Chronovores	Quantum !The Quantum Archangel	Serbo-Croatian and Slovenian for master
Keith Potter		Quantum !The End of the Line
Kreer !Major Kreer	used when allied with the Tzun in 1950s America.	First Frontier
Castillo !Template:Frontier		Housewarming
Seta !Mr Seta	Used aboard the starship Gallery	Dust Breeding	Anagram of master
Smith, John !Dr John Smith	Used while amnesiac on an unnamed colony world	Master
Bruce	occasionally reverted to impersonation of a San Franciscan paramedic named Bruce after he had taken over Bruce's body	Doctor Who
Don Maestro	Whilst trapped on Earth in the 20th century.	Mastermind	Italian for master in the sense of teacher
Dr Harcourt De'ath	to practice eye surgery on many patients, in order to literally "have eyes everywhere"	Time's Horizon, Eyes of the Master	Bar the apostrophe, De'ath is spellt the same way as "Death."
Kappa Chi	Designation as CIA agent.	The Death of Hope
The Doctor	Whilst masquerading as a future incarnation of the Doctor.	Dominion
Yana !Professor Yana	chameleon arch identity	Utopia	Had no known meaning of its own, but the Face of Boe made up an acronym, "You Are Not Alone"
Harold Saxon	used to win Prime Ministership of the United Kingdom	Love & Monsters - Last of the Time Lords	Mister Saxon was a coincidental anagram of Master No Six; Harold is a derivative of Old English Hereweald meaning Master of the Armies. The Anglo-Saxons were invading England during the reign of King Arthur
Missy	New name adopted after regenerating into female form	Deep Breath - Present	Short for "Mistress", a female form of "Master".
Mobile Intelligence Systems Interface	Ruse allowing close contact with and delaying recognition by the Doctor	Dark Water	Backcronym from the above

Behind the scenes

• During Anthony Ainley's tenure as the Master, pseudonyms made from anagrams of "Tony Ainley" were often used in the credits — both on-screen and in Radio Times — for the Master's disguises, such as Neil Toynay for the Portreeve in Castrovalva.
• Another, craftier pseudonym was used in Radio Times for The King's Demons, when Sir Gilles was listed as being played by "James Stoker" — an anagram of "Master's Joke".
• On Big Finish's Sympathy for the Devil, the pseudonyms are back. This time, Mark Gatiss, who voiced an alternate version of the Master, is credited as "Sam Kisgart".