Etymology of "pistol"

Hand cannon from the Chinese Yuan Dynasty (1271–1368).

Multiple senses of the word "pistol"

     The word "pistol" is often synonymous with the word "handgun". Some handgun experts make a technical distinction that views pistols as a subset of handguns. Sometimes in American usage, the term "pistol" refers to a handgun whose chamber is integral with the barrel, making pistols distinct from the other main type of handgun, the revolver, which has a revolving cylinder containing multiple chambers. However, CommonwealthWebley Mk VI was "Pistol, Revolver, Webley No. 1 Mk VI", and the designation "Pistol No. 2 Mk I" was used to refer to both the Enfield Revolver and the later Browning Hi-Power semi-automatic.
     The first pistols were made as early as the 15th century, but their creator is unknown. By the 18th century, the term came to be used often to refer to handheld firearms. Practical revolver designs appeared in the 19th century, and it was in that century that the (sometimes-observed) technical differentiation in usage from the words "pistol" and "revolver" developed, at that time differentiating the newer revolver from the single-shot pistols previously in use.