Man of Honour

Man of Honour: a mafioso, a "made man" in one of the Italian-origin crime families. So-called because one upon a time they considered their 'profession' to be an honourable one, providing service to their communities in exchange for 'Pizzo', protection money. As they now mostly scam and squeeze people, it's become a dark joke.

Paulie: "That rat bastard Marco still owes me $200! I'll fuckin kill him!"
Joey: "hey hey hey, forgettaboutit! Marco's a Man of Honour} now, cross him and you'll be sleeping with the fishes"