Generally speaking, the abdomen refers to the lower abdomen, which is three inches below the navel. When I say three inches, I mean the size of your body, that is, the combined width of your index finger, middle finger, ring finger and little finger.
Zhongdian Day is the midpoint of Zhongshan Mountain, the middle position of the chest, parallel to the two nipples.
To the abdomen is the position of eyebrows, the third eye of Erlang God, and to the head is the position of pineal gland.