pocket gun

In American English, a pocket pistol is any small, pocket-sized semi-automatic pistol (or less commonly referencing either derringers, or small revolvers), and is suitable for concealed carry in either a coat, jacket, or trouser pocket.Pocket pistols are sometimes categorized as smaller than sub-compact pistols, but the distinction is not clear cut as some small sub-compact pistols may be categorized as pocket pistols, and some large pocket pistols may be classified as sub-compact pistols.Pocket pistols were popular in the United States until the 1960s and 1970s, when most states passed laws limiting or prohibiting the carry of concealed weapons. However, the passage of "shall issue" firearms license laws in the 1980s and 1990s, resulted in a resurgence in the popularity of pocket pistol in the United States, creating new markets for small, simple, reliable, concealed carry firearms.
In general use, the term pocket pistol is purely descriptive, but "mouse gun" (used especially for those of the smallest calibers) is often a pejorative. Likewise, pocket pistols, due to their small size, often are lumped in with Saturday night specials, another pejorative term, which are typically inexpensive small caliber handguns.

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