Definition - What does Jala mean?
Jala is Sanskrit word which can mean “not real” or “jugglery,” but can also refer to water. It is most commonly used in yoga to refer to jala neti and jala basti, which are both cleansing practices for the body that involve water.
These practices are described at length in the "Hatha Yoga Pradipika," as well as other yogic texts. They form part of the Hindu shatkarma, which is the yogic system of bodily cleansing practices.
Yogapedia explains Jala
Jala neti literally means “water cleansing." It involves pouring lukewarm saltwater into one nostril and tilting the head so that it streams out through the other. This is performed on both sides, then the nasal passageways are cleared through rapid breathing practices. Jala neti helps remove excess mucous and debris, helping prevent sinus problems and colds. It is said that jala neti also has profound effects on the mind, bringing greater clarity and mental well-being.
Jala basti, on the other hand, is water cleansing of the colon that's performed by sucking water through the anus using a catheter tube. It is mentioned in the "Hatha Yoga Pradipika," which claims it has many beneficial effects, including increasing the appetite, curing digestive disorders, and purifying the senses and mind.