1. The act of emptying, clearing of the contents, or discharging. Specifically: (a) (Mil.) Withdrawal of troops from a town, fortress, etc. (b) (Med.) Voidance of any matter by the natural passages of the body or by an artificial opening; defecation; also, a diminution of the fluids of an animal body by cathartics, venesection, or other means. 2. That which is evacuated...