pocket holster

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.

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