TheThe Great Compendium of Acupuncture and Moxibustion (针灸大成 zhēn jiǔ dà chéng)lists ST-27 as being appropriate for treatment of distention and swelling in the small intestine and for treatment of kui shan. From this it can be seen that the point name may indicate the location of the point at the largest part of the lower abdomen. The point’s function of freeing the intestines can be affirmed in translating the character 大 (dà) as to free orunblock. (康熙字典 Kāng Xī Zì Diàn).
One alternate name for ST-27, 液门 (yè mén) is rendered here as Humor Gate. The point may have acquired this name because it can be used to treat vexation thirst, which arises when humor is depleted. It is more likely, however, that 液门 is a mistranscription of the alternate name 腋门 (yè mén), which is rendered here as Armpit Gate. 腋门 is the name for ST-22 found in the oldest extant acupuncture book, the The Systematic Classic of Acupuncture and Moxibustion (针灸甲乙经 zhēn jiǔ jiā yǐ jīng). The difference between 液 and 腋 is only that the former has a water radical on its left (three dots), while the latter has the radical 月 (ròu), flesh, on its left. In addition, the two characters are homophones and could have been easily confused. TB-2 also has these two point names but in that case the name 液门 is older and 腋门 is probably a mistranscription. See acupoint names: origins, meanings, and translations.