Rat. Dope. Booze. Gun moll. Shakedown. The popularity of these terms in American English is due, in part, to an obscure Boston lawyer who, perhaps as a lark, published a slim dictionary of criminal slang in 1908. Joesph M. Sullivan's limited published output plays an important role in American criminal slang. His terms and definitions are widely cited in dictionaries, scholarly papers, and the popular media. This book presents the contents of Sullivan's "Criminal Slang: A Dictionary of the Vernacular of the Under World" as first published by the Detective Pub. Co. in 1908. The original content been extensively annotated to include considerable new information Sullivan presented in two additional publications, as well as to clarify ambiguity in Sullivan's original texts. All of Sullivan's slang terms and definitions are, for the first time, presented here in a single authoritative, alphabetized listing. An introduction puts Sullivan's work into historical context, along with a bibliography of American criminal slang dictionaries and glossaries from 1859-1918. A series of original illustrations demonstrates Sullivan's skill in choosing words for his dictionary by charting the growth the growth for several of his terms from 1860 to the present.