Do you know where your Dan Tian is? Part II of TCM Terminology

The Dan Tian is an area in the lower abdomen a bit more than an inch below the navel between the spine and navel. It is the area where jing is stored represented by the uterus in women and the chamber of essence (sperm) in men.

Ancient Taoist texts often mention three dan tian, the first being the lower dan tian mentioned above, the second is the middle dan tian which stores qi at the level of the heart. The brain is considered the third or upper dan tian which is said to be the sea of marrow.

There are actually "four seas" in TCM called Si Hai. Often referred to a group of acupuncture points where the qi gathers as if converging like water in the sea. The Si Hai are as follows

Sui Hai - sui refers to marrow therefore sui hai is sea of marrow and as mentioned above refers to the brain.
Xue Hai - xue means blood, the sea of blood may refer to the liver where blood is stored, the chong meridian where the blood of all channels is seen to converge or an acupuncture point on the spleen meridian above the knee.
Qi Hai - qi as discussed in Part I has many translations, the sea of qi is represented by the centre of the chest as mentioned above, as well as an acupuncture point on the ren meridian located just below the navel.
Shui Gu Zhi Hai - shui translates as water and gu as grain. Therefore shui gu zhi hai is the sea of grain and water which refers to the stomach where food is received and stored.

Ming Men is another an important area of the body often referred to as the gate of life. Ming translates as life, fate, destiny, order, command and Men means door or gate. The life gate or Ming Men is located on the back between the two kidneys and is considered to store a person's jing or essence and therefore the source of qi and root of yin and yang.

Wu Xin translates as five hearts, wu means five and xin can be translated as heart, the mind, feeling, intention, centre. Wu Xin actually refers to the palms, soles of the feet and centre of the chest and plays an important diagnostic role in certain conditions.