腎

Phono-semantic compound consisting of:

肉 (⺼) — semantic component, representing flesh or body parts, indicating relation to an internal organ.

臤 (어질 현 / 견) — phonetic component, giving the sound shèn / sin and carrying the sense of firmness, strength, or endurance.

According to Shuowen Jiezi (說文解字):

「腎，腰腸之間也。从肉臤聲。」

“腎 is located between the waist and intestines. Formed from 肉 (‘flesh’) and phonetic 臤.”

In oracle bone and bronze forms, the shape of 腎 roughly depicted the outline of the lower back or paired organs in the waist area, confirming its anatomical reference to the kidneys.

腎臟 (신장) — kidney (organ)

腎氣 (신기) — kidney energy; vital essence (esp. in traditional medicine)

腎虛 (신허) — deficiency of kidney energy

腎炎 (신염) — nephritis, kidney inflammation

腎功能 (신기능) — renal function

腎石 (신석) — kidney stone

補腎 (보신) — to tonify or nourish the kidneys

腎經 (신경) — the kidney meridian (in Chinese medicine)

In traditional Chinese medicine (中醫), the kidneys (腎) are not limited to the physical organs but represent one of the body’s fundamental energies — the storehouse of essence (精) and the source of vitality, reproduction, and growth.

From Huangdi Neijing (《黃帝內經·素問》):

「腎者，作強之官，伎巧出焉。」

“The Kidneys are the officials of strength; from them arise skill and ability.”

This portrays 腎 as the root of physical power and creative potential.

「腎藏精，主生殖。」

“The kidneys store the essence and govern reproduction.”

Hence, 腎 governs both 生命力 (vital force) and 性功能 (sexual function) — the sustaining core of human life.

Philosophically, 腎 is paired with 水 (Water) among the Five Elements (五行), symbolizing depth, stillness, and the potential for renewal.

In Daoist alchemy, to “nourish the kidneys” (養腎) means to preserve one’s essence (守精) and maintain balance between 陰 and 陽 energies.

In classical literature, 腎 sometimes appears metonymically to represent endurance or inner strength, the “hidden foundation” of life.

Thus, 腎 stands not only for a physical organ but for the source of vitality and reproduction — the quiet root from which human life draws endurance and renewal.