In the Adak vow, one asks Allah for support and promises to perform a "good" deed as soon as this wish has been fulfilled. The term Adak is common in Turkish-speaking countries and Nadhr in Arabic.
An adak is obligatory and must be performed. A sacrificial animal is usually designated as an adak. It can also be a donation of money or just fasting for a few days. The meat of the sacrificial animal must be distributed in full to the needy.
