Chou Collection, Upper Volume Radical: Mouth (kǒu) Character: yu Kangxi strokes: 15 Page 208, Entry 20 Pronounced yu. According to the Erya: Explaining Ancient Words (Erya Shigu), yu means danger. Also, according to the Guangyun: General Rhymes (Guangyun), it refers to the chirping of birds. Also, according to the Guangyun: General Rhymes (Guangyun) and the Jiyun: Collected Rhymes (Jiyun), pronounced shu. According to the Guangyun: General Rhymes (Guangyun), it means danger.