一切經音義 3.212

3.212

法蠃（魯和反說文蝸牛類而形大案蠃者樂器也吹作美聲以和眾樂故引為喻經作螺俗字者也）。

Dharma conch (pronounced 魯 + 和 fanqie. The Shuowen says: “Belongs to the snail family, but of large size.” Examining the conch: it is a musical instrument; blowing it produces a beautiful sound that harmonizes with all the music, hence it is used as an analogy. In the sūtra text it is written as '螺', which is a popular character.)