一切經音義 20.48

20.48

拇指（上矛厚反蒼頡篇云拇將指也賈逵注國語云拇大指也說文云從手母聲經本從木作拇非也）。

拇指 ("thumbs"; [the former] fanqie: 矛 + 厚. The Cangjie pian says: "Mu (拇) means the leading finger." Jia Kui's Commentary to the Guoyu says: "Mu means the thumb (big finger)." The Shuowen says: "It takes 手 as semantic and 母 as phonetic." In the sūtra text it is written with 木 as 拇, which is incorrect).