Naga, in Buddhism, is the Sanskrit word for a deity taking the form of a great snake, specifically the multi-headed king cobra. The Buddhist naga has the form of a great cobra, usually depicted with a single head but sometimes with many heads. The naga which is seen sheltering the Buddha while meditating is known as Mucilanda. Mucilanda is believed to have protected the Buddha from the elements like rain and storm after he attained enlightenment. It is said that the four weeks after the Buddha began meditating under the Bodhi tree, the heavens darkened for seven days, a heavy rainfall started. The mighty king of the serpents, Mucilanda then is believed to have emerged from beneath the earth and protected the Buddha with his hood as the Buddha is considered the source of all protection. When the storm stopped, the serpent king Mucilanda assumed his human form, bowed before the Buddha and returned to his palace in joy.