filing margin
Technical term used in engineering drawing for the margin area reserved for filing or binding.
図面の用紙枠は、左側を広めに取るのが一般的です。
In engineering drawings, the filing margin is generally set wider on the left side.
Compound of 用紙 (paper, form) and 枠 (frame, margin). The exact historical derivation is uncertain; the term is a modern technical coinage.