"Dainichi," meaning "Great Solar Disk," embodies an evolved form of Vairocana, the Buddha associated with the sun. In Esoteric Buddhism, Dainichi Nyorai symbolizes the truth of the universe, serving as its very embodiment. Moreover, it is believed that all life originates from Dainichi Nyorai, and other Buddhas, including Shakyamuni Buddha, are considered emanations of Dainichi Nyorai.
Dainichi Nyorai has two distinct aspects within the realm of attaining enlightenment. "Kongokai Dainichi Nyorai" symbolizes the wisdom essential for enlightenment, represented by the term "kongou" which means diamond, signifying its unbreakable nature. On the other hand, "Taizokai Dainichi Nyorai" represents boundless compassion, much like how all existence is enveloped in a mother's womb. These dual aspects, "kongou" and "taizokai," intertwine to form the core of Dainichi Nyorai's significance as the principal deity in the perspective of Esoteric Buddhism.