"The term derringer is a genericized misspelling of the last name of Henry Deringer, a famous 19th-century maker of small pocket pistols. Many copies of the original Philadelphia Deringer pistol were made by other gun makers worldwide, and the name was often misspelled; this misspelling soon became an alternative generic term for any pocket pistol, along with the generic phrase palm pistol Deringer's competitors invented and used in their advertising."@en . . . .