Dhauti is an important part of the Shatkarma (sometimes known as Shatkriya), the yogic system of body cleansing techniques. It is intended mainly to the cleaning of the digestive tract in its full length but it affects also the respiratory tract, external ears and eyes. According to Gheranda Samhita, it is divided into four parts called:
a. Antar (internal) dhauti
Vatsara dhauti, swallowing air into the stomach and expelling it through the anus after passing it through the intestines.
Varisara dhauti (aka shankhaprakshalana), evacuating a large quantity of water through the bowels. It can be further subdivided into laghoo shankhaprakshalana, a short form in which only six glasses of warm saline water are taken and expelled, and poorna shankhaprakshalana, the full form in which sixteen glasses are taken and expelled.
Vahnisara dhauti (aka agnisara kriya), rapidly breathing in and out while simultaneously expanding and contracting the abdomen in such a way that resembles the panting of a dog.
b. Danta (teeth) dhauti
Danta dhauti is the cleaning of the teeth by usual methods. It also includes:
Jihva dhauti, cleaning the tongue,
Karna dhauti, cleaning the ears,
Kapalrandhra, cleaning the upper back portion of the palate,
Chakshu dhauti, bathing the eyes with tepid saline water or urine.
c. Hrid (cardiac or chest region) dhauti
Vastra dhauti, cleaning the stomach by swallowing a long thin strip of cloth and retiring it after a while.
Danda dhauti, cleaning the oesophagus, from the throat to the stomach, by inserting a specially prepared stick.
Vaman dhauti (aka vyaghra kriya), regurgitating the solid food contents of the stomach. It is called kunjal kriya if performed on a stomach empty of solid food, having taken only four to six glasses of warm saline water.
d. Moola shodhana (rectal cleansing)
Moola shodhana, cleaning the rectum with the middle finger or a turmeric root.
Bahiskrita dhauti, a very difficult technique, involves pushing the rectum out and washing it in the hands.
Definition courtesy Wikipedia.