bonk/oif

bonk/oif /bonk/, /oyf/ interj.  In the {MUD}
   community, it has become traditional to express pique or censure by
   `bonking' the offending person.  Convention holds that one should
   acknowledge a bonk by saying `oif!' and there is a myth to the
   effect that failing to do so upsets the cosmic bonk/oif balance,
   causing much trouble in the universe.  Some MUDs have implemented
   special commands for bonking and oifing.  See also {talk mode}.