Nutter

Common usage: A Nutter is usually someone performing stunts, while often not dangerous, sometimes not too sane. The use of the word varies, from person to person. Some consider it an insult while others take it as a complement to their apparent disrespect for their own personal safty. Some consider it as offensive as a swear word. However in England there are at least 17 Nutter Streets, Roads, Lanes or Cresents.

Alernative usage: Obsession: A person obsessed with a perticular item/sport/concept it the point of knowing a maddening amount of knowleadge about the said topic could be referred to as a form of nutter. Usually pre-fixed with the said item/sport/concept. Example: A Formula 1 fan, who knows all the drives and their respective teams, starting positions and finishing places for all races for the last 20 years, could be (and I dare say, should be) refered to as a Formula 1 Nutter.

Other usage: A name, usually a last/surname.