Palm gun

A pocket pistol is an American term for any small, pocket-sized semi-automatic pistol or, less-popular, any other handgun (e.g., derringer, or small revolver) of (most commonly) small caliber, suitable for concealed carry in either a front or rear pocket of a pair of trousers, or in an exterior coat pocket. Many consider the term solely applicable to subcompact, single-stack, hammerless handguns that are striker-fired in semi-automatic blowback configurations. However, with the advent of newer and smaller double action only (DAO) semi-automatic pistol designs, locked breech concealed-hammer pistol designs of the same subcompact single-stack size are now also called pocket pistols.

In general use, the term pocket pistol is not considered a pejorative term. However, some pocket pistols, often those of lesser caliber, are referred to as mouse guns, which sometimes is considered a pejorative term among those who prefer larger caliber pistols, although not among those who prefer smaller caliber pistols for deeper concealment.

The pocket pistol originated in the mid-17th century as a small, concealable flintlock known as the Queen Anne pistol, the coat pistol, or the pocket pistol. This was used throughout the 18th century, evolving from a weapon reserved for the wealthy to a common sidearm in broader use as more and more manufacturers made them by the start of the 19th century.

The original 19th century vest-sized pocket pistol, the derringer, which developed from the Philadelphia Deringer, is typically no longer widely used for concealed carry (except in .357 Magnum calibers) with most preferring more rounds of small caliber cartridges in an auto-loading pistol design to provide increased self-defense capability extending beyond one or two shots. While still retaining moderate amounts of popularity, short-barreled ("snubnose") revolvers are similarly not as widely used as pocket pistols today as they were during the 1950s and earlier.

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