續一切經音義 7.169

7.169

閒谷（上古晏反韻集云溝㵎也爾雅云山夾水曰澗或作澗字俗用亦通下古鹿反玉篇山谷也爾雅曰水注谿曰谷又谷養也老子云谷神不死是為玄牝也）。

閒谷 (The upper character is pronounced with the fanqie gu + yan. The Yunji says: "A ravine or gulley." The Erya says: "A stream enclosed by mountains is called a 澗." Sometimes written as 澗, which is also accepted in common usage. The lower character is pronounced with the fanqie gu + lu. The Yupian says: "A mountain valley." The Erya says: "Water pouring into a stream is called a valley [谷]." Also, 谷 means to nourish. Laozi says: "The valley spirit never dies; this is called the mysterious female").