1 definition by TheoPham

Opposite of big brain. Smooth brain refers to an idiot or someone dumb. Neuroscientists believe the more folds you have in your brain means the smarter you are. Therefore if you are called smooth brain, you have less folds and therefore dumb.
How did you forget to lock the door? Good move, smooth brain.

You don’t know basic math? Smooth brain 🙄
by TheoPham September 14, 2019
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