When your mother nags at you to do something and asks the trick question, " Are you hearing me clearly?" You reply, "Oh what? Sorry. I was at my brain beach."
by McWritah July 9, 2015
When one has spent too much time at the beach and feels lazy and tired due to overexposure to the elements.
"Bruh, I spent all day at the beach chasin' them swells and now I have beach brain. I can't even think straight, hombre"
by dj bradford August 22, 2015