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• D-day
  D-day

  noun

  the day, usually unspecified, set for the beginning of a planned attack.
• D-Day
  D-Day

  The code name for the first day of a military attack, especially the American and British invasion of German-occupied France during World War II on June 6, 1944 (see invasion of Normandy). This marked the beginning of the victory of the Allies in Europe. Germany surrendered less than a year later.

D-day

American  

[dee-dey] / ˈdiˌdeɪ /

Or D-Day

noun

1. Military. the day, usually unspecified, set for the beginning of a planned attack.

2. June 6, 1944, the day of the invasion of western Europe by Allied forces in World War II.

3. Informal. any day of special significance, as one marking an important event or goal.

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D-day British  

noun

1. the day, June 6, 1944, on which the Allied invasion of Europe began

2. the day on which any large-scale operation is planned to start

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D-Day Cultural  

1. The code name for the first day of a military attack, especially the American and British invasion of German-occupied France during World War II on June 6, 1944 (see invasion of Normandy). This marked the beginning of the victory of the Allies in Europe. Germany surrendered less than a year later.

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Etymology

Origin of D-day

First recorded in 1918; D (for day ) + day; the same pattern as H-hour

Example Sentences

See Examples For:

D-day D-Day

“Pressure,” the new World War II movie from director Anthony Maras and writer David Haig, is a hyperfocused look at the days leading up to D-day with a special focus on the weather.

From Los Angeles Times ● May 29, 2026

After Stagg convinces the leaders to postpone D-day, he is vindicated by a deluge of rain that arrives while everyone is attending church at Southwark House on June 5.

From Los Angeles Times ● May 29, 2026

In the film, Scott’s Stagg arrives at Southwark House from Dunstable four days before D-day is planned.

From Los Angeles Times ● May 29, 2026

“That was an absolute disaster and yet we remember D-day as one of the great military triumphs in history,” Haig says.

From Los Angeles Times ● May 29, 2026

Few of us slept the night before D-day.

From "Code Talker: A Novel About the Navajo Marines of World War Two" by Joseph Bruchac

The nomination included the five D-Day beaches known by their code names: Utah, Omaha, Gold, Juno, and Sword.

From Barron's ● Jul. 26, 2026

The iconic D-Day landing beaches in Normandy were on Sunday inscribed on UNESCO's World Heritage List, marking the culmination of a project launched nearly two decades ago.

From Barron's ● Jul. 26, 2026

Every June, to commemorate D-Day, the Abilene community gathers on the lawn of the Eisenhower Library and Museum.

From The Wall Street Journal ● Jun. 14, 2026

Around the anniversary of the D-Day invasion on June 6, the whole place turns into a love-fest for America.

From Salon ● Jun. 9, 2026

By July 10, 1944, one month after the D-Day invasion, the Allies controlled most of Normandy.

From "Hitler Youth: Growing Up in Hitler's Shadow" by Susan Campbell Bartoletti