D-day

or D-Day

[ dee-dey ]

noun

Military. the day, usually unspecified, set for the beginning of a planned attack.
June 6, 1944, the day of the invasion of western Europe by Allied forces in World War II.

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

Origin of D-day

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

Words Nearby D-day

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use D-day in a sentence

It must have been one of the big highs of the war, to be in London and hit the pubs during the last two months before D-day.
Blood in the Sand: When James Jones Wrote a Grunt’s View of D-Day | James Jones | November 15, 2014 | THE DAILY BEAST
For the citizens of that city, this event has a deeper, more sentimental meaning than even D-day.
Who Liberated Paris in August 1944? | | August 24, 2014 | THE DAILY BEAST
Williams interviewed and profiled four D-day veterans, showing his sensitive side without ever seeming maudlin.
Hillary Clinton’s Network Massage | Tom Shales | June 10, 2014 | THE DAILY BEAST
D-day was the first successful opposed landing on French territory—the country was held by the Nazis—in over 800 years.
D-Day 70th Anniversary Celebrations: Queen, Obama, Merkel, Putin and Cameron in France | Tom Sykes | June 6, 2014 | THE DAILY BEAST
D-day was 70 years ago, and to midshipmen of today, it is all but ancient history.
D-Day Historian Craig Symonds Talks About History’s Most Amazing Invasion | Marc Wortman | June 5, 2014 | THE DAILY BEAST

The end of a perfect D-day she tried to grin, her teeth chattering with cold.
Dorothy Dixon and the Mystery Plane | Dorothy Wayne

British Dictionary definitions for D-day

D-day

noun

the day, June 6, 1944, on which the Allied invasion of Europe began
the day on which any large-scale operation is planned to start

Origin of D-day

C20: from D (ay) -day; compare H-hour

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Cultural definitions for 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.

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