dunkirk

a crisis in which a desperate effort is the only alternative to defeat; "the Russians had to pull off a Dunkirk to get out of there"

a seaport in northern France on the North Sea; scene of the evacuation of British forces in 1940 during World War II

an amphibious evacuation in World War II (1940) when 330,000 Allied troops had to be evacuated from the beaches in northern France in a desperate retreat under enemy fire