the highest form of owning. the ladder of humiliation goes like this: diss-toast-roast-own-pwn-pizzowned. Pizzowned can only be used in the past tense, because of its massiveness. Being pizzowned rarely happens, and when it does, the victim either craps their pants or cries like a little baby. If you say you've pizzowned someone, you're probably lying. I've never pizzowned someone, either, so stop lying to yourself.
To be completely owned by the use or involvement of a piano
This can involve dropping a piano on someones head or slipping over when drunk and bashing your head on the piano
Often used when someone playing the piano mucks up the piece due to the unwanted involvement of a third person (usually mocking/shouting)