When you feel like your getting dumber when a funny comment is said.
Boy 1: Bro, monkeys don't pay taxes.
Boy 2: HAHAHAHA
Boy 2: I'm having a brain leak right now
by Uncorruptedmikey October 8, 2021
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When something you ment to think in your head comes out loud, creating a rather awkward situation.
Guy 1: I totally brain leaked last night while screwing my girlfriend

Guy 2: Aww man what you say?
Guy 1: Accidently said "Battenburgs are what make my life complete" about 7 minutes in
Guy 2: I'm Surprised you last 7 minutes

Guy 1: Wait what?
Guy 2: Sorry Brain Leak
by AshleysMexicanDick October 24, 2014
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