1) To do or say something ridiculously stupid.
2) To sleep on a pillow that has actual shit inside it as a substitute for feathers and catch pinkeye as a result.
3) To complete sexual favours for your stepdad.
4) To be so fat that you have to have extra wide doors fitted in your house.
Example of number 1
Mum "Where did you come in the race son?"
Kid "I came 1th mum!"
Example of number 3
Stepdad "Come here kid I've got some smegma on my penis that you need to come and lick off."