Grangemouth Munch Share definition Flag A Grangemouth Munch is a meal consisting of cigarette butts, dirt, shit, cum and broken buckfast bottles all microwaved in the local radioactive pile slapped into a stew Friend: what you eating?It a Grangemouth munch, ya dopey cunt. Grangemouth Munch by Crackheed March 14, 2019 Get the Grangemouth Munch mug.