tra·bec·u·la·tion \ ̷ ̷ˌ ̷ ̷ ̷ ̷ˈlāshən\noun (-s) Etymology: New Latin trabecula + English -ation 1.: the formation of trabeculae in the lumen or on the walls of an organ (as the bladder) 2.: trabecular condition < the characteristic of trabeculation of the spleen >