magnum

noun

1. 1.A bottle of wine containing 1.5 liters of fluid, double the volume of a standard bottle.
2. 2.A powerful firearm cartridge, often derived from a shorter, less powerful cartridge calibre that uses the same bullet.
3. 3.A handgun that fires a cartridge of this calibre; chiefly a revolver, but rarely an autoloader firing an unusually powerful calibre.