rifle cartridge UK /ˈɹaɪ.fəl ˈkɑː.tɹɪd͡ʒ/US /ˈɹaɪ.fəl ˈkɑɹ.tɹɪd͡ʒ/ noun1 •A firearm cartridge primarily designed and intended for use in a rifle/carbine, or machine gun. formsrifle cartridges