Si Collection, Upper Volume
Radical: Water (shuǐ)
Entry: shi
Kangxi stroke count: 13
Page 637, Entry 18
Pronounced zhi.
According to the Explaining Graphs and Analyzing Characters (Shuowen Jiezi), it refers to water that is clear enough to see the bottom. Another definition describes it as the appearance of maintaining integrity.
In the Book of Odes (Shijing), in the section Odes of Bei (Beifeng), the text mentions that the Jing River is turbid compared to the Wei River, with its sandy islets (zhi) appearing clear and still. The commentary explains this as holding firmly to one's principles and original intentions, remaining as steady and unmoving as an islet.
In the Classified Dictionary of Characters (Leipian), it is noted that this character is sometimes written in a variant form.