a defect, deficiency, or inadequacy; something missing or incomplete that causes a problem or prevents proper functioning
申請書に不備があったため、再提出を求められた。
Because the application had deficiencies, I was asked to resubmit it.
点検で不備が見つかったので、部品を交換した。
A defect was found during the inspection, so we replaced the part.
納品書に不備がないか、よく確認してください。
Please check carefully that there are no omissions or errors on the delivery note.
an old valediction or closing phrase used at the end of a letter (now rare)
古い文書の末尾に『不備』とだけ書かれている例が見つかった。
I found an example of an old document that only had '不備' written at the end.