Thieves' cant

Thieves' cant or rogues' cant, also known as peddler's French, was a secret language (a cant or cryptolect) which was formerly used by thieves, beggars and hustlers of various kinds in Great Britain and to a lesser extent in other English-speaking countries. The classic, colourful argot is now mostly obsolete, and is largely relegated to the realm of literature and fantasy role-playing, although individual terms continue to be used in the criminal subcultures of both Britain and the U.S. Its South German and Swiss equivalent is the Rotwelsch and Serbo-Croatian equivalent is Šatrovacki.