| Noun | 1. | Marne River - a World War I battle in northwestern France where the Allies defeated the Germans in 1918First World War, Great War, War to End War, World War 1, World War I - a war between the allies (Russia, France, British Empire, Italy, United States, Japan, Rumania, Serbia, Belgium, Greece, Portugal, Montenegro) and the Central Powers (Germany, Austria-Hungary, Turkey, Bulgaria) from 1914 to 1918 France, French Republic - a republic in western Europe; the largest country wholly in Europe |