The Ziyuan (; or "Essays on Chinese Characters") was a Chinese dictionary attributed to the Eastern Jin Dynasty scholar Ge Hong. The original text was lost, and the small modern "Ziyuan" recension has 34 headwords, mostly Chinese Buddhist loanword terminology. 
The "Ziyuan" is notable for having the first occurrence of the Chinese borrowing "ta" (; "tǎ"; "t'a"; "tower; pagoda"). Feng (2004:205) classifies "ta" as a "monosyllabic phonemic loanword," and notes:
塔/"ta"/=浮屠/"futu"/=浮图/"futu"/=佛图/"futu"/=数斗波/"shudoupo"/=兜婆/"doupo"/：Buddhist tower: "塔,佛堂也 [The "ta" is Buddhist tower]" (字苑), "作九层浮图 To build the Buddhist tower with nine levels" (水经注), "塔亦胡言, 犹宗庙也. ["ta" comes from languages of Hu nationalities, it means tower.]" (魏书). It was borrowed from "buddhastupa" of Sanskrit. The process of pronunciation change is as follows: "Buddhastupa" "stupa" "tupa" "t’ap". 