In the world of the nefarious, there is a distinct pecking order.
At the top level, we have the Godfather. He has bosses who report to him and his is the final word of authority on all things. Below him, we have the bosses. Bosses come with lots of different titles, whether they go by don, jefe, or the man, these guys are sort of like the regional governors.
Then, then there are the underlings. These are the soldiers who make things happens. At the bottom, there are the minions. These guys are the cannon fodder, the red shirts. Next, there are lackeys, the grunts that lead the minions. They don't have to be smart, they just need to be good at getting people to get things done. Above them, there are the henchmen, who are higher up the food chain than lackeys but their roles aren't nearly as well defined. These guys can work for underbosses or directly for the bosses, but it seems as though they don't usually have people command of other guys.
It seems that I'm missing things. If you can think of what, let me know.