Brig Bain Share definition Flag When your brain is to big to be a big brain so it's a Brig Bain/Brain Hemorrhage/A fetus eating your brain "I have a Brig Bain!""Well you're f***ing dead""Yay!" Brig Bain by Chemosworstnightmare May 24, 2020 Get the Brig Bain mug.