("tube") is
a colloquial term for "tube." In general, any pipe or tube, whether in
plumbing or in the human circulatory system, is referred to as a nadi.
When it comes to the Hindu idea of the subtle body, a nadi
has a more specific connotation.
The subtle body is a separate physiological system from
gross matter that corresponds to the material body.
It exists on a different level than gross matter.
It is made up of six psychic centers (chakras), which are
seen as multipetaled lotus flowers that run approximately down the spine and
are joined by three vertical channels called nadis.
The ida nadi is located on the left, the pingala nadi is
located on the right, and the sushumna is located in the middle.
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