World War II

American  

noun

1. the war between the Axis and the Allies, beginning on September 1, 1939, with the German invasion of Poland and ending with the surrender of Germany on May 8, 1945, and of Japan on August 14, 1945. WWII

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World War II British  

noun

1. Also called: Second World War.  the war (1939–45) in which the Allies (principally Britain, the Soviet Union, and the US) defeated the Axis powers (principally Germany, Italy, and Japan). Britain and France declared war on Germany (Sept 3, 1939) as a result of the German invasion of Poland (Sept 1, 1939). Italy entered the war on June 10, 1940 shortly before the collapse of France (armistice signed June 22, 1940). On June 22, 1941 Germany attacked the Soviet Union and on Dec 7, 1941 the Japanese attacked the US at Pearl Harbor. On Sept 8, 1943 Italy surrendered, the war in Europe ending on May 7, 1945 with the unconditional surrender of the Germans. The Japanese capitulated on Aug 14, 1945 as a direct result of the atomic bombs dropped by the Americans on Hiroshima and Nagasaki

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World War II Cultural  

1. A war fought from 1939 to 1945 between the Axis powers — Germany, Italy, and Japan — and the Allies, including France and Britain, and later the Soviet Union and the United States. The war began when the Germans, governed by the Nazi party, invaded Poland in September 1939 (see invasion of Poland). Germany then conquered France, using blitzkrieg tactics, and forced a desperate British withdrawal at Dunkirk. The Germans tried to wear down the British by heavy bombing, but the British withstood the attacks (see Battle of Britain). The Soviet Union signed a treaty with Adolf Hitler but entered the war on the side of the Allies after Germany invaded Russia in 1941. The United States was drawn into the war in 1941, when the Japanese suddenly attacked the American naval base at Pearl Harbor. Japan made extensive conquests in east Asia but was checked by American victories at the Battle of Midway Island and elsewhere. The German invasion of Russia was halted at the Battle of Stalingrad. Allied forces took much of Italy in 1943, forcing its surrender. Beginning with the invasion of Normandy in 1944 (see D-Day), the Allies liberated France from German occupation and pressed on in Europe, defeating the Germans in the Battle of the Bulge and elsewhere. Germany surrendered in May 1945 (see V-E Day). The war in the Pacific ended in September 1945 (see V-J Day), after the United States dropped atomic bombs (see also atomic bomb) on the Japanese cities of Hiroshima (see also Hiroshima) and Nagasaki. In the aftermath of World War II, more constructive and less punitive measures were applied to the defeated countries than after World War I (see Marshall Plan, Nuremberg trials, and United Nations).

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The political leaders of the war included Winston Churchill of Britain, Adolf Hitler of Germany, Benito Mussolini of Italy, Franklin D. Roosevelt of the United States, and Joseph Stalin of the Soviet Union. The military leaders included Charles De Gaulle of France; Bernard Montgomery of Britain; Hermann Goering and Erwin Rommel of Germany; Tito of Yugoslavia; and Omar Bradley, Dwight Eisenhower, William Halsey, Douglas MacArthur, Chester Nimitz, and George Patton of the United States.

Example Sentences

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World War II

After World War II, Federal Reserve officials wanted to stop helping the Treasury Department keep interest rates low, leading to a fierce struggle with the Truman White House.

From MarketWatch ● Aug. 21, 2026

A dispute between a producer and Netflix over a missing copy of a World War II spy drama starring Nicolas Cage has now reached the Los Angeles Police Department.

From Los Angeles Times ● Aug. 21, 2026

It was the latest jolt to South Korea’s confidence in an alliance that has formed a cornerstone of Washington’s defense strategy in Asia since the end of World War II.

From Los Angeles Times ● Aug. 19, 2026

At the height of World War II, students in Miss Lillian Craig’s fifth-grade class in Roanoke, Va., wrote to America’s top soldier, Gen. George C. Marshall: How did he select the nation’s senior generals?

From The Wall Street Journal ● Aug. 18, 2026

World War II was a battle between two groups of countries—the Allies and the Axis.

From "At Last She Stood" by Erin Entrada Kelly