1. About as batshit insane as one can get without being locked in a padded room. One who is headmental acts in an erratic and unpredictable way, so much so that it isn't even funny. They are also observed to say things which blatantly aren't true and often hold grudges over the tiniest things.

2. The state your ex will enter approximately two weeks after impact.
1. Bob: Mutiliate the innocent! I think that I speak for all of us when I say the Phantom Menace was the best Star Wars. I have five nipples.
Jen: Uh-oh, he's gone head mental...

2. I'm sorry, I do love you, just not like that. I love you as a friend, as a brother maybe. I do hope we can still keep some sort of relationship as I'd hate to have hurt you too much.
by The King of Carrot Flowers December 23, 2005
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