A word you can say as blasphemy or profanity without getting into any trouble. It is also a popular thing to say at home, typically if your parents aren't there.
Internet chat-speak for owned, which means "the act of totally dominating an oponent". Pwn is pronounced "pown" or "puh-won", and t0t4l f00k1n pWnAgE is pronounced "total fooking pownage".