Nāga is the Sanskrit and Pāli word for a deity or class of being, taking the form of a very great snake—specifically the king cobra, found in Hinduism, Buddhism, Jainism and Sikhism. The Hindu epic the Mahabharata frequently characterizes nagas as having a mixture of human and serpent-like traits. The great nemesis of the nagas in the Mahabharata is the gigantic eagle-king Garuda although Garuda and the nagas began life as cousins.
The serpent king Vasuki helped the gods to recover amrita, the elixir of immortality, from the Ocean of Milk by serving as the cord they wrapped around Mount Mandara in order to churn up the depths of the ocean. (Book I: Adi Parva, Section 18.) Nāgas live in Pātāla, the seventh of the nether dimensions or realms. They are the children of Kashyapa and Kadru. Vishnu is originally portrayed in the form sheltered by a Śeṣanāga or reclining on Śeṣa, but the serpent is a common feature in Ganesha iconography and Shiva is often shown garlanded with a snake.
Nagas are objects of great reverence in South India, where it is believed that they bring fertility and prosperity to their venerators. Expensive and grand rituals like the Nagamandala are conducted in their honor; certain communities called Nāgavanśī, trace their ancestry to nāgas.
In India, nāgas are considered nature spirits and the protectors of springs, wells and rivers. They bring rain, and thus fertility, but are also thought to bring disasters such as floods and drought.Traditions about nāgas are also very common in all the Buddhist countries of Asia. In many countries, the nāga concept has been merged with local traditions of great and wise serpents or dragons such as the Burmese nat . In Tibetan religion, the nāga was equated with the klu that dwell in lakes or underground streams and guard treasure. In China, the nāga was equated with the Chinese dragon. For Malay sailors, nāgas are a type of dragon with many heads; in Thailand and Java, the nāga is a wealthy underworld deity. In Laos they are beaked water serpents. In a Cambodian legend, the nāga were a reptilian race of beings who possessed a large empire or kingdom in the Pacific Ocean region.
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