An Australian word started at Xavier College, Melbourne that means 'as if', and denotes disbelief. Can be used widely. Can also be used instead of 'rolled','wrecked' or 'owned'
Tim: I could have any girl in this room.
Matt: Yelse! (or Yelse you could).
'Yeh he totally yelsed me' (proved me wrong)
'He's in need of a yelsing' (needs to be put in his place)
Jon: Let's go to the football.
Pat: Yelse to that! (No let's not!)