I wouldn't have guessed that this word would have the implications that it does. Interestingly, there isn't any mention of the common usage I see in World of Warcraft which sticks much more strictly to the very first part of the definition. Perhaps there will be an addition later if the word persists in the gaming vernacular.
Aggravation, aggression; deliberate trouble-making or harassment (esp. formerly by skinhead gangs: see BOVVER), violence, trouble; annoyance, inconvenience.