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

The beginning of the end of World War II occurred 80 years ago Thursday, when roughly 160,000 Allied troops made landfall in Normandy on D-day.

From Los Angeles Times • Jun. 6, 2024

"Well guys, it's official. D-day has come and gone. It's gone past five o'clock, Monday. No contract has been signed," Fury said on Instagram.

From BBC • Sep. 26, 2022

In late 2020, as Flash D-day drew near, supporters scrambled to rescue it.

From Slate • Feb. 5, 2021

Indeed, on a single day this week, more Americans died of COVID-19 than were killed on 9/11 or D-day.

From Los Angeles Times • Dec. 11, 2020

The ministers argued among themselves that night—the evening before the march that James Bevel had called D-day.

From "While the World Watched: A Birmingham Bombing Survivor Comes of Age during the Civil Rights Movement" by Carolyn Maull McKinstry