revolver -
a door consisting of four orthogonal partitions that rotate about a central pivot; a door designed to equalize the air pressure in tall buildings
A revolver is a repeating firearm that has a cylinder containing multiple chambers and at least one barrel for firing. As the user cocks the hammer, the cylinder revolves to align the next chamber and round with the hammer and barrel, which gives this type of firearm its name. In modern revolvers, the revolving cylinder typically chambers 5 or 6 rounds, but some models hold 10 rounds or more.
