Zi Collection, Upper Volume, Page 11, Entry 01 Radical: Cliff (hǎn) Pronounced gu (falling tone) Also explained in the "Guangyun" (Guangyun) and "Zhengyun" (Zhengyun) as pronounced an gu (entering tone). Also explained in the "Jiyun" (Jiyun) as pronounced yu wu (entering tone). The character "wu" and "yu" are the same character. "Shuowen Jiezi" (Shuowen Jiezi) originally wrote it as "yu", meaning a small defensive work. Another explanation refers to a low city wall. Also explained in the "Zhengyun" (Zhengyun) as a bend in a mountain. Also pronounced ai du (falling tone) in the "Guangyun" (Guangyun), with the same pronunciation as "wu". The meaning is the same.