ETYM Latin evacuatio: cf. French évacuation.
Removal of civilian inhabitants from an area liable to aerial bombing or other hazards (such as the aftermath of an environmental disaster) to safer surroundings. The term is also applied to military evacuation, as occurred for example when Allied troops were evacuated from the beaches of Dunkirk in 1940. People who have been evacuated are known as evacuees.
The act of evacuating; leaving a place in an orderly fashion; esp. for protection.