一切經音義 95.108

95.108

洙泗（上樹儒反下音四二水名杜注左傳云洙在魯國下縣西南禮記曾子責子夏云吾與尒事夫子於洙泗之間是也說文二字竝從水朱四皆聲也）。

The Zhu and Si Rivers (洙: fanqie 樹儒 [zhū]; 泗: pronounced 四 [sì]; names of two rivers. Du [Yu]'s commentary on the Zuozhuan says: "The Zhu River is southwest of Xiazhai in the state of Lu." The Liji recounts Zengzi rebuking Zixia, saying: "I served the Master with you between the Zhu and Si Rivers," which is this. The Shuowen jiezi states: "Both characters are composed of 水 ('water') with 朱 and 四 phonetic respectively").