Yīn chuāng (Yīnchuāng) (-)
original: 音窗
tuning-hole
Literal translation: 音: "sound/tone"; 窗: window; Each of the ventholes in pipes that are, for "aesthetic (i.e. symmetry) reasons", longer than necessary for their pitch.
Wong, Samuel Shengmiao: Qi’ - An instrumental guide to the Chinese orchestra. Singapore, 2005, p.139 (yinchuang).
张跃进 [Zhāng Yuèjìn]: 笙教学教程 [Shēng jiàoxué jiàochéng; Shēng teaching course], 北京 (Běijīng), 2012, p.3.
汉英词典 (Hàn Yīng cídiǎn) / A Chinese-English dictionary. 北京 [Běijīng], 1985, p.826 & 107.