Calibre or caliber is the diameter of a gun barrel. Calibre or caliber may also refer to: Science and technology Caliber (artillery), a measure of barrel diameter and length Caliber (horology), a designation of clockwork movements Caliber (mathematics), a cardinal κ associated with a topological space Calibre (software), an ebook manager and editor Arts, entertainment and media Calibre (musician) (born Dominick Martin), Northern Irish drum and bass producer Calibre (film), a 2018 thriller film Comics Caliber (Radical Comics), a comic book limited series from Radical Comics Caliber Comics, an American comic book publisher Calibre (comics), an Azteca Publications character Caliber, a Marvel Comics supervillain and enemy of Alpha Flight Other uses Caliber 40, an American sailboat design Dodge Caliber, a model of car Calibre (menswear), Australian clothing company See also Caliper, a measurement device Kaliber (disambiguation) Opel Calibra, a car