"Our Thing" or "This Thing Of Ours". The real name for the Mafia. Cosa Nostra is a crime sydicate that began in Sicily
in the mid nineteenth century. A "Made Man" is a man that has become a member of Cosa Nostra. According to original Cosa Nostra rules, you had to be of Sicilian descent to be a member, you couldn't have a close relative that was a police officer, etc. Many political leaders have been murdered by Cosa Nostra.
Kiss the Don's ring or die. This is Cosa Nostra.