Nadis
Nāḍī (Sanskrit नाडी nāḍī = tube, pipe; Tamil
i/ˈ/naadi) நாடி = nerve, blood vessel, pulse: pronounced with long vowel sounds and a retroflex 'd') is 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.
Nadi is an important concept in Hindu philosophy, mentioned and described in the sources some of which have about 3,000 years of history. The amount of nadis of the human body are claimed to be up to hundred-of-thousands and even millions. In regard to Kundalini yoga, there are three important nadis: ida, pingala, and sushumna (for the alternate names, see the section below). Ida (इडा, iḍā "comfort") lies to the left of the spine, whereas pingala (पिङ्गल, piṅgala "tawny (brown)", "golden", "solar") is to the right side of the spine, mirroring the ida. Sushumna (सुषुम्णा, suṣumṇā "very gracious", "kind") runs along the spinal cord in the center, through the seven chakras. 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.
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