What is the definition of "Cosa Nostra"?

Search: cosi nostra

Why: Tonight on "Gossip Girl," GG said:

Just like the mob, New York prep schools have their own Five Families. You may be the John Gotti of Constance, Little J, but that doesn't mean you'll ever be part of this Cosa Nostra.

Answer: In many Italian publications the term "Cosa Nostra" is used to distinguish the Sicilian Mafia from other criminal networks that are also sometimes referred to as "mafias."

According to Google Translate:

nostra - our
cosca - clan

Source: Wikipedia

The More You Know: Do you know all the Five Families? They are:

1. Bonanno: Vincent Basciano (Salvatore Montagna is the acting boss)
2. Gambino: Peter Gotti (Ruling Committee/Panel - Daniel "Danny" Marino, John Gambino, Bartolomeo "Bobby" Vernace)
3. Colombo: Carmine "Junior" Persico (Thomas Gioeli is the acting boss)
4. Genovese: Daniel Leo
5. Lucchese: Vittorio "Vic" Amuso (Ruling Committee/Panel - Aniello "Neil" Migliore, Joseph "Joey Dee" DiNapoli, Matthew Madonna)

Some of the images for these people are pure dynamite.