What is the Taoist diagram of yin and yang called?

The Taoist diagram of yin and yang is called the taijitu.

The familiar circular black-and-white design represents the complementary relationship of yin and yang. Each side contains a dot of the opposite color, expressing the idea that yin contains yang and yang contains yin, and that each can transform into the other.

The Chinese term taijitu means “diagram of the supreme ultimate.” Although the symbol is strongly associated with Taoism today, its familiar visual form developed through a long history of Chinese cosmological and philosophical diagrams rather than appearing fully formed in the earliest Taoist texts.

Taijitu is often confused with the bagua, an arrangement of eight trigrams used in Chinese cosmology and associated with the Yijing. The two symbols can appear together, but they are not the same diagram.