Zi Collection, Upper Volume Radical: Knife (dāo) Pronounced zāo (falling tone) Explanation: In the "Zi Hui Bu" (Zihuibu), it is used like a knife to cut, with the pronunciation zāo. The "Shuo Wen Jie Zi" (Shuowen Jiezi) explains it as completing a celestial cycle. It is now written as zāo. Zhui.