According to the "Guangyun" (Guangyun), it is pronounced with the characters "fu" and "wu" cut together. In the "Jiyun" (Jiyun), it is pronounced with the characters "feng" and "wu" cut together, with a pronunciation identical to "fu" (fu). The "Yupian" (Yupian) explains it as "yifu". The "Guangyun" (Guangyun) states that it is the same as "fu" (fu), referring to the front flap of clothing. Furthermore, the "Guangya" (Guangya) mentions "fu" (fu) and "la" (la) as referring to a sword sheath. The "Jiyun" (Jiyun) records that it is sometimes written as "ce" (ce).