Bon Grasson Share definition Flag French version of the Irish saying "Good Craic" which means to have a jolly good time. Pierre: This nightclub smells of garlic. Luc: Ahh bon grasson! Bon Grasson by akaRed January 23, 2009 0 0 Get merch Get the Bon Grasson mug. Buy Now — $32.95 See more merch