Guangyun uses the characters "niú" and "jī" for the fanqie, and Jiyun uses the characters "xīn" and "yí" for the fanqie, pronounced the same as "yí" (rising tone). Guangyun explains it as the buttocks. Jiyun explains it as an alternative name for the buttocks. Also, Wuyin Jiyun uses the characters "xiāng" and "yì" for the fanqie, pronounced the same as "xì" (falling tone). It means to moan.