According to the "Guangyun" and "Jiyun," it is marked as gu lù qiè, pronounced the same as "gǔ." The "Yupian" explains it as the instep of the foot. Also, the "Jiyun" marks it as tú gǔ qiè, pronounced the same as "dú." The meaning is the same. Also, the "Yupian" marks it as hú mù qiè, and the "Jiyun" marks it as hú gǔ qiè, pronounced the same as "gǔ." It refers to the hind leg of livestock. Also, the "Wuyin Jiyun" marks it as kǔ jiǎo qiè, pronounced the same as "kē." It refers to leather armor. It also has the meaning of striking downwards. Another explanation is white raw silk.