I was just watching an old episode of Criminal Minds and there was this description of cults:
"Cults commonly have their own language. They invent or redefine certain words only the cult members understand. It's a way of isolating the members from outsiders. It's a very powerful form of thought control."
Ironically, JWs redefine the very word "cult" out of necessity, saying it can only apply to a group with a SINGLE charismatic leader = Therefore, they aren't a cult!