do not
Depicts a knife (刀) cutting with drops of blood coming out, based on the original meaning "cut throat", now written as 刎. The current meaning is a phonetic loan.
《說文》:“勿,州里所建旗。象其柄,有三游。雜帛,幅半異。所以趣民,故遽稱勿勿。,勿或从。”
cut throat