turtlehead sneak Share definition Flag A fart that is surprisingly accompanied by a turd, forcing the farter to pull it back in to prevent a larger accident from ocurring. Luckily for Eric, he realized his fart was a turtlehead sneak before he stained his underwear. turtlehead sneak by Ulmelqlo April 30, 2008 Get the turtlehead sneak mug.