The AI-powered English dictionary
plural open cities
(military, international law) A city which has announced it has abandoned all defensive efforts, generally in the event of the imminent capture. quotations
“You needn’t worry about bombs, by the way. Dresden is an open city. It is undefended, and contains no war industries or troop concentrations of any importance.”
1969 March 31, Kurt Vonnegut, Jr., Slaughterhouse-Five […] (A Seymour Lawrence Book), New York, N.Y.: Delacorte Press, page 127