OVILEXIA Share definition Flag (o vil eks' e uh) n. The uncontrollable urge to lean out the car window and yell "Baa!!" every time you pass a sheep.See also bovilexia Diane's ovilexia provided entertainment to the rest of the passengers every time they drove past Black Sheep Meadows. OVILEXIA by runeStorm July 5, 2017 Get the OVILEXIA mug.