Ida Nadi

One of the vertical channels (nadi) in
the traditional conceptions of the subtle
body. The subtle body is an alternate
physiological system believed to reside
on a different plane of existence than
the actual body, but with certain correspondences to it. It is visualized as a set
of six psychic centers (chakras) running
roughly along the course of the spine,
connected by three parallel vertical
channels. Above and below these centers are found Shiva (awareness) and
Shakti (power), the latter as the latent
spiritual energy known as kundalini.
The ida nadi is the vertical channel
on the left side of the body. As with
the rest of the subtle body, the ida nadi
has certain symbolic correspondences;
in particular, it is identified with the
moon and is thus visualized as being
light in color.