d day

/ˈdiˌdeɪ/
noun
  1. June 6, 1944, the day during World War II when Allied forces invaded Normandy, France, beginning the liberation of Western Europe from Nazi control.
    • D-Day was the largest seaborne invasion in history.
    • We visited the D-Day memorial in France to honor the veterans.
    • Many soldiers lost their lives on the beaches of Normandy on D-Day.
  2. A day on which an important or decisive event is planned to take place.
    • For the students, exam day felt like their own personal D-Day.
    • The team worked all night to get everything ready for D-Day.
    • We've been preparing for months, and tomorrow is D-Day for our product launch.
Synonyms
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