Answer

In Jain Dharma, a 6-day fast is commonly called Chhath or Chhath Upvas.

Explanation

It means observing fasting continuously for six days, usually taking only boiled water during permitted times, according to one’s capacity and guidance.

Spiritual Understanding

Such tapasya is practiced for purification of karma, strengthening self-control, and deepening detachment from bodily comforts.

Takeaway

A 6-day fast is called Chhath Upvas in Jain tradition.