Nadi (yoga)
Nāḍī (Sanskrit नाडी nāḍī = tube, pipe; Tamilinaadi) நாடி = nerve, blood vessel, pulse) are a term for the channels through which, in traditional Indian medicine and spiritual science, the energies of the physical body, the subtle body and the causal body are said to flow. Within this philosophical framework, the nadis are said to connect at special points of intensity called nadichakras. The concepts of a subtle body and a causal body are not recognised terms used in conventional science or medicine.
The word "nadi" is pronounced as "nāḍī", with long vowel sounds and a retroflex 'd'. They are an important concept in Hindu philosophy and are mentioned and described in numerous texts going back about 3,000 years to the earliest scriptures. All texts explains that there are a large amount of nadis present in the human bodies, some claims hundred-of-thousands, some millions. In regard to Kundalini yoga, there are three important nadis: ida, pingala, and sushumna. Ida (इडा, iḍā) lies to the left of the spine, whereas pingala (पिङ्गल, piṅgala) is to the right side of the spine, mirroring the ida. Sushumna (सुषुम्णा, suṣumṇā) runs along the spinal cord in the center, through the seven chakras – Muladhara at the base, and Sahasrara at the top (or crown) of the head. Under the correct conditions the energy of kundalini is said to uncoil and enter sushumna through the brahma dwara or gate of Brahma at the base of the spine.