Chou Collection, Upper Volume Radical: Mouth (kǒu) 叮 Kangxi strokes: 5 Page 172, Entry 11 According to the Guangyun (Guangyun), Jiyun (Jiyun), and Zhengyun (Zhengyun), pronounced ding. According to the Yupian (Yupian), the term dingning means to instruct or exhort. It is also commonly written as dingning. As seen in the Biography of Lang Ji in the History of the Later Han (Houhan shu), repeatedly exhorting and paying close attention to this matter.