Any institution duly licensed, certified, and operated as a hospital. The term hospital does not include a convalescent facility, nursing home, or any institution or part thereof which is used principally as a convalescence facility, rest facility, nursing facility, or facility for the aged. An institution for the care and treatment of ill, injured, infirm, mentally abnormal, or deformed persons, with organized facilities for diagnosis and surgery and providing 24-hr nursing service and medical supervision.