Utlaga is a term used by the Elders to describe someone that they banish/or set a bounty on. It's literal translation in Latin is "an outlaw", or "wolf's head." which is essentially its meaning in the series. Dr. John Dee, Billy the Kid, Niccolò Machiavelli and Mars Ultor are the only known beings to be declared Utlaga, by their masters for disappointing them.
It means Oath Breaker in the language of Danu Talis.