Turbid yīn

Turbid substances within the body as distinct from clear substances referred to as clear yáng. Plain Questions (素问 sù wèn, yīn yáng yìng xiàng dà lùn) states, Clear yáng issues from the upper orifices; turbid yīn issues from the lower orifices. Clear yáng effuses through the interstices; turbid yīn pervades the five viscera. Clear yáng fills the four limbs; turbid yīn flows to the six bowels. From this, it can be seen that turbid yīn refers to the waste products of the body discharged in the form of urine and stool. In some contexts, it also refers to the blood. See turbid qì goes to the heart.