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urgent; pressing; immediate; prompt; express
urgently; promptly; at once; right away; without delay; as soon as possible
至急対応が必要な案件が発生しました。
An urgent matter requiring immediate attention has arisen.
至急連絡をくださいとメールが来た。
I received an email saying to contact them urgently.
この書類は至急で送る必要があります。
This document needs to be sent urgently.