cholecystocolostomy cho·le·cys·to·co·los·to·my (kō'lĭ-sĭs'tō-kə-lŏs'tə-mē) or co·lo·cho·le·cys·tos·to·my (kō'lō-kō'lĭ-sĭ-stŏs'tə-mē) n. The surgical formation of a communication between the gallbladder and the colon.