It is the universal symbol with metaphysical qualities and is another name for serpent. It is the creature that represents a circle when asleep but straightens when awaken.
What is Naga ?
It represents a circle, the female principle, a phallus the male principle and the ‘sperm’ when in motion. In Hinduism the snake is the symbol of the eternal cycle of time and immortality. It is worshipped as a divine r semi divine being regarded as a deity of the rain and guardian of the riches of earth. In southern India it is symbol of fertility and in north a protective symbol. Shiva though is the lord of serpents. The Cobra is his emblem as well as that of Kali, his consort. In the Hindu kingdom of Nepal it is not the cobra, it is the Naga Raja which is worshipped during Nagpanchami festival.
In Tantric discipline, the snake is regarded as a deity, it represents the mystical female energy and is known as Shakti, coiled at the bottom of the spinal column is known as Kundalini. Manasa is the serpent Goddess, her followers are called Nagas those who practice Tantrism.