1, Yin, the ancient name of Yin and Yang in China, is called "all Yin in eight characters". The year, month, day and hour of a person's birth are each matched with heavenly stems and earthly branches, a total of eight characters, hence the name.
2. Shi Yang is a Chinese vocabulary, pronounced yáng shí, which comes from Selected Works of Zhang Heng and is interpreted as Xia Zhishi in spring; When the weather is warm.
Extension:
China used "heavenly stems" and "earthly branches" in traditional precepts. There are ten "heavenly stems", which are divided into five yin and five yang. A, C, E, G, nonyl Yang; B, D, D, Xinhe. There is a branch of 12, which is divided into 6 yin and 6 yang. Zi, Yin, Chen, Wu, Shen, Xu Yang; Ugly, ugly, awkward, unfinished, unitary, yin. "heavenly stem" is referred to as "stem" and "earthly branch" is referred to as "branch".
Baidu Encyclopedia-Yin Shi