位い置ち決ぎめ孔こう

noun

index hole; positioning hole

Technical term in computing and manufacturing for a hole used to align or position components, such as in floppy disks or mechanical assemblies.

• フロッピーディスクの位い置ち決ぎめ孔こうが破は損そんすると、読よみ取とりができなくなる。

  If the index hole of a floppy disk is damaged, it becomes unreadable.