"Taiji" is the conjunction of opposites, "yin" and "yang", in Chinese cosmology and martial arts. It is heavily related to the concept of "Aiki" and "Ju" in Japanese martial arts.

Many Chinese martial arts practice the expression of "taiji", as a state of balance in the body manifesting both "yin" and "yang" simultaneously, such as in the moderm Chinese martial art of Taichi Chuan, which itself has several distinct family lineages, but which is certainly not the only category of Chinese martial arts to practice it. Other example of Chinese martial arts that express these concepts would be Bagua Quan, Xingyi Quan, and more.