This should be used in place of shotgun not. It used when you are with a group of people and you don't want to do something, with 'notgun' coming before the action. The last person to not call 'notgun' has to do this action.
Dave: Notgun ordering the pizza!
Fred: Notgun ordering the pizza!
Jane: Notgun ordering the pizza!
Paul: Shit, there's no-one else here, I guess I have to order the pizza...
Fred: Notgun ordering the pizza!
Jane: Notgun ordering the pizza!
Paul: Shit, there's no-one else here, I guess I have to order the pizza...
by rorz758 July 14, 2006
Exclaimation used when one specifically does not want the shotgun seat in a car, most often in a cab. The last person to call "notgun" has to sit upfront with the cabbie and will most likely get stiffed with the fare.
by Marion Cobretti July 24, 2006