This is the biggest festival of Assam. This word is probably derived from the Sanskrit word Viṣuvat. Though three Bihus are celebrated, the Bahāg Bihu (or Bohag Bihu), also called Sout (or Caitra) which comes in the spring season—April—is the biggest of the three festivals. It falls on the last day of Caitra. This is celebrated over seven days. The first day is reserved for the worship and special care of the cattle. The second is a day of big feast for friends and relatives. On this day it is usual to patch up differences by social calls. The tribals celebrate it with special songs and dance, called Husari Bihuna. Next in importance is Māgh Bihu, also called Bhogālī Bihu, celebrated on the last day of Puṣya and the first day of Māgha. Piling up firewood to form a temple-like structure (called meji) and setting fire to it is an important part of this festival. The whole day is spent in feasting. Last comes the Kaṭṭi Bihu or Kāṅgāli Bihu in autumn (in Kārttīka). A special feature of this celebration is the worship of the tulasī (basil) plant and placing of lighted lamps at its base. A ‘sky lamp’ is hung over a high bamboo pole, not only to light up one’s yard, but also to guide the dead to the next world!