gabooosh Share definition Flag An idiot who believes Simple Plan only inspires teenagers. Taken from a Simple Plan message board: "DuDe Simple Plan Inspiers everybody not just teenagers! Idiot... You Sound like a Preppy gabooosh." gabooosh by Drucilla October 22, 2006 0 0 Get merch Get the gabooosh mug. Buy Now — $32.95 See more merch