interior region of the body too deep to be reached by acupuncture
肓 refers to a deep, inaccessible region inside the body, specifically the area between the heart and diaphragm that is beyond the reach of acupuncture needles.
肓 combines 亡 (to lose, disappear) with 月 (flesh/body part), suggesting a hidden or lost region within the body. The exact historical development is uncertain.
The top 亡 looks like a lid covering something, and the bottom 月 is flesh. Imagine a sealed-off, hidden chamber deep inside the body where no needle can reach.
For コウ, picture a deep, hidden cove inside the body: cove -> コウ, a place too deep to reach.
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