A bastardization of the word prawned/pwned/powned/owned. Basically meaning the same as every other MMORPG slang word, to kill or "beat down" extremly well.
When having a conversation with somebody and someone states something so fucking asinine it completely derails all forms of thought by all parties involved.
John: So what is the definition of a Fish Hook?
Jordan: It's when people were fishing off the docks near the Boston Tea Party and they saw the British coming toward them so they decided to Teaspoon Leg it out of there and get a hooked finger in their mouths.
Miles: Whaaaaaaa....
Adam: O.o
John: You.. You just Blained this entire fucking show.
Jordan: You're welcome.