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deadline; closing; cut-off
closing (a door, window, etc.)
cofferdam
締め切りに間に合うように頑張ります。
I will work hard to meet the deadline.
応募の締め切りは今週の金曜日です。
The application deadline is this Friday.
締め切りを過ぎると受け付けません。
Applications will not be accepted after the deadline.