A shyster [shahy-ster] is a slang word for someone who acts in a disreputable, unethical, or unscrupulous way, especially in the practice of law, politics or business. The etymology of the word is not generally agreed upon. The Merriam-Webster Dictionary says it is based on the German ‘Scheißer’ (literally ‘defecator’ but also used to refer to deceivers), but the Oxford English Dictionary describes it as ‘of obscure origin,’ possibly deriving from a historical sense of ‘shy’ meaning disreputable. Various false etymologies have suggested an anti-Semitic origin, but there is no proof for that. One source claims that the term originated in Philadelphia in 1843 from a disreputable attorney named ‘Schuster.’
Notable ‘shysters’ of fiction include Sylvester Shyster (a Walt Disney cartoon character introduced in 1930), a disbarred attorney who schemes to deprive Minnie Mouse of her inheritance; and Dave Kleinfeld, a mob lawyer in ‘Carlito’s Way’ (1993) who was parodied in ‘Grand Theft Auto: Vice City’ as Ken Rosenberg.