Si Collection, Upper Volume Radical: Water (shuǐ) Entry: zi Kangxi Strokes: 19 Page 658, Entry 19 According to Rhyme Dictionary (Jiyun) and Collection of Rhymes (Yunhui), the pronunciation is ci (falling tone), referring to a sluice gate for drainage. Another interpretation states that still water is called zi. According to Augmented Rhymes (Zengyun), it means to obstruct water.