Chou Collection, Middle Volume Radical: Earth (tǔ) Entry: 墺 Kangxi stroke count: 16 Page 239, Entry 25 Ancient character: 圫 Pronounced ao (falling tone). Fertile land in the four directions suitable for living. Also, a water bank is called ao. Pronounced yu (entering tone). Meaning is the same. In the Book of Documents (Shangshu), written as ao. In the History of the Former Han (Hanshu), written as ao.