Definition of Pistol

Right side of Colt Lightweight Stainless Commander pistol.
Russ Chastain

Definition

A pistol is a handgun--but not all handguns are pistols.

The defining factor that makes a handgun a pistol is a cartridge chamber that is integral with the barrel. Semi-automatic handguns have a barrel with the chamber built in, which means fall into the category of pistols. Revolvers, on the other hand, are not pistols, because a revolver contains a cylinder that's separate from the barrel and which contains multiple chambers that rotate around to align the cartridge with the barrel as the gun is fired.

When it comes to firearms terminology, any gun that is designed to be fired using one or both hands, without shouldering the gun, is a handgun. Legal definitions of the term may vary in certain locales.

The term "pistol" is often erroneously used to describe any handgun, but strictly speaking, its definition should preclude its use to describe revolvers or any other any type of handgun that does not have a chamber made integral with the barrel.

The category of handguns known properly as pistols includes semi-automatic, break action, bolt action, rolling block, falling block, and other various action types, and they are often single shot guns. A lever-action rifle that's had the stock removed to become a handgun (like the "mare's leg" used by Steve McQueen in the television series "Wanted: Dead or Alive") would qualify because its chamber is part of its barrel.