Tangyun states that this character is pronounced ji (falling-rising tone), with the same pronunciation as the character for already (ji). Shuowen Jiezi explains: a condition where breath flows backward during eating, preventing smooth respiration, is called the character for gasping (gui). The shape of the character is the character for lack (qian) written in reverse. The commentary mentions that after evolving into the clerical script, it is written as the character for nothing (wu). Zi Collection, Page Position: Upper Radical: Lack (qiàn) Page 603, Entry 01