vas·ti·tude \ˈvastəˌtüd, ˈvaas-, ˈvais-, ˈvȧs-, -stə.ˌtyüd\noun (-s) Etymology: Latin vastitudo, from vastus vast + -tudo -tude 1.: the quality or state of being vast : immensity < the vastitude of the concept held him spellbound > 2.: a vast extent or space < all that vastitude of wilderness — Walter O'Meara >