Nandi, according to a Siddhantic tradition, was is the chief guru of the eight disciples of Nandinatha Sampradaya, namely, Sanaka, Sanatana, Sanandana, Sanatkumara, Tirumular, Vyagrapada, Patanjali, and Sivayoga Muni, who were sent in eight different directions, to spread the wisdom. The Chamites of Vietnam believe that when they die, Nandi will come and take his soul to India.

The word Nandi comes from the Tamil root word Nandhu, which means to grow or appear. In the Sanskrit word nandi, the divine guardian of Shiva-Nandigan has the same meaning. The worship of Shiva and Nandi can be traced back to the Indus Valley civilization. There are many bull-seals found in Harappa and Mohenjo daro, which indicate that the practice of worshipping the god has been around for thousands of years.

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