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2.
a general term to describe when your brain is engaged, but you aren't getting anywhere.

a) where you can't make a decision ... usually because there is too much information to process

b) where you can't even get a grip on a problem because it is beyond the scope of your brain.
Diane - I slept like crap last night.

Mike - Oh? Too bad. Was it from gut rot from that jalepeno shrimp or brainspin from your BCP exercises at work??

Diane - Definitely brainspin. I just can't get a handle on the whole BCP thing. It is sooooo complicated.

Mike - Why don't you just past it off to your boss? Let him handle it?

Diane - Are you kidding!?!? He's such a PHB, he tries to divide by zero. This would brainspin his head right off his shoulders.
by karbyn February 16, 2010
 
1.
The inability to sleep because of your mind fixating on a thought.
The Lost finale gave me brainspin and I wasn't able to sleep all night.
by Loogaroo June 22, 2010