一切經音義 5.192

5.192

欠㰦（下音去埤蒼云欠㰦張口也經從口作呿桂苑珠叢云呿是臥聲也韻詮云呿睡聲也非此義宜改從欠作㰦案此二字皆是出氣互用亦通）。

Yawning (欠㰦: the second character has the sound 去. The Picang states: "Qianqu (欠㰦) means opening the mouth wide." The sūtra text writes it with the radical 口 as 呿. The Guiyuan zhucong states: "呿 is the sound of sleeping." The Yunquan states: "呿 is the sound of slumber." This is not the meaning here; it should properly be changed to have the radical 欠, written as 㰦. Note that both characters refer to expelling breath; interchangeable usage is also acceptable).