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The unavoidable consequence of male aging wherein one's cranium enlarges to grotesque proportions and career options dwindle.
Friend: Dude, what's wrong with your head? You look hydrocephalic, or something.

Me: No, but I just turned 41...

Friend: Oh, then it's probably just you're getting Shatner Head.

Me: Is it terminal?

Friend: Yes.
by gakr May 24, 2013