作さく戦せん開かい始し日び

noun

start day for military operation; departure day; D-Day

Military term for the scheduled day a military operation begins; can also be used metaphorically for any important launch day.

• 作さく戦せん開かい始し日びは来らい週しゅうの月げつ曜よう日びに決きまった。

  The start day for the operation has been set for next Monday.

• プロジェクトの作さく戦せん開かい始し日びを社しゃ内ないで発はっ表ぴょうした。

  We announced the project's launch day internally.