Chou Collection, Middle Volume. Radical: Earth (tǔ). 堀. Kangxi strokes: 11. Page 231, Entry 21. Guangyun, Jiyun, and Zhengyun: Pronounced ku (rising tone). Same as ku (cave). A hole or cavern. Zuo Commentary (Zuozhuan), Year 27 of Duke Zhao: Prince Guang of Wu hid armored soldiers in a cavernous room to feast the king. History of the Former Han (Qianhan shu), Biography of Zou Yang: Hiding and dying in cavernous holes and among rocks and bushes. Also, Guangyun: Pronounced ju (falling tone); Jiyun, Yunhui, and Zhengyun: Pronounced jue. To rush forth or protrude. Song Yu, Rhapsody on the Wind (Feng fu): Rushing and billowing, dust rises. Note: Here, rushing corresponds to rising, and billowing corresponds to dust. Various scholars define the term as dust, which is incorrect.