一切經音義 37.36

37.36

仙窟（下困骨反毛詩云窟穴也考聲云土窟室也說文窠也從穴屈聲或從土作堀亦通俗字）。

Immortal's cave (仙窟) (The lower character is kun + gu fan. The Mao Shi states: "A 窟 is an earthen cave." The Kaosheng states: "An earthen cave chamber." The Shuowen states: "A nest or burrow. Composed with 'hole' [穴] semantic and 屈 phonetic." Sometimes written with 'earth' [土] as 堀, which is also an interchangeable vulgar character).