The Spleen is one of the zàng organs stipulated by Traditional Chinese Medicine

Traditional Chinese medicine

Traditional Chinese Medicine refers to a broad range of medicine practices sharing common theoretical concepts which have been developed in China and are based on a tradition of more than 2,000 years, including various forms of herbal medicine, acupuncture, massage , exercise , and dietary therapy...

 (TCM). It is a functionally defined entity and not equivalent to the anatomical organ of the same name.

In the context of the zang-fu concept

As a zàng, the Spleen is considered to be a yin

Yin and yang

In Asian philosophy, the concept of yin yang , which is often referred to in the West as "yin and yang", is used to describe how polar opposites or seemingly contrary forces are interconnected and interdependent in the natural world, and how they give rise to each other in turn. Opposites thus only...

 organ. Its associated yang organ is the Stomach

Stomach (Chinese medicine)

Stomach, a concept from traditional Chinese medicine as distinct from the Western medical concept of stomach, is more a way of describing a set of interrelated parts than an anatomical organ....

. Both Liver and Stomach are attributed to the Earth element.

Regarding its stipulated functions, the Spleen

• governs ‘’transportation and absorption‘’ (运化), i.e. the extraction of jīng weī (精微, lit. ‘’essence bits‘’, usually translated with food essence, sometimes also called jīng qì [精气, essence qi]) - and water - from food and drink, and the successive distribution of it to the other zàng organs.
  • the jīng weī constitutes a large part of the body's acquired qì (the other part coming from breathing, by facilitation of the Lung zàng). In this spirit, the Spleen is also called "root of the postnatal" (后天之本, ]) - as opposed to the congenital qì, which is stored by the Kidney zàng. The Spleen absorbs jīng weī from the food after it has been preprocessed by the Stomach and the Small Intestine, and then distributes it to the whole body, especially upwards to the Lung and Heart, where jīng weī is transformed into qì and xuě (blood). Thus, TCM also describes the Spleen as the source of ‘’production and mutual transformation‘’ (生化) of qì and xuě.
  • the Spleen distributes the water extracted from the food and distributes it to the whole of the body, especially to the Lung and Kidney zàng, and thus assists the body's water metabolism.
• ‘’contains‘’ (统) the blood inside the vessels (this is also one of the functions of qì)
• governs muscles and limbs
• opens into the lips (and mouth)
• houses the yì
  Yi
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  (意, ‘’thinking‘’)
• governs pondering (思)

Its associated body fluid is saliva.

The Spleen's function (i.e., the Spleen-qì) is said to be strongest between 9 and 11am.
When the Spleen is functioning well, digestion will be good, the muscles will be strong and circulation will be efficient. Dysfunction of the Spleen typically presents as diarrhea, malnutrition, edema, weak/atrophic muscles, greasy taste in the mouth, or excessive bleeding. The Spleen is especially weakened by the Pathogenic Factor Dampness.