The fuzzy logic that dominates your thought process on a Sunday, usually the result of a long Saturday night.
Rob: Yo Liam, why did you order chicken fried steak from the 5-point. Bad order man. What were you thinking?
Liam: I dunno. Sunday Brain I guess.
Liam: I dunno. Sunday Brain I guess.
by Comeonfeelthe August 22, 2008
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