also: キリトリせん
noun
cut-off line; perforated line; dotted line
A printed line on paper, often perforated or dotted, indicating where to cut or tear. Common on forms, tickets, and coupons.
申込書の切り取り線に沿って切り取ってください。
Please cut along the cut-off line on the application form.
この
Please detach this ticket along the perforated line.