taboo
Taboo is a unique phenomenon in China feudal society, which began in Zhou Dynasty, became in Qin Dynasty, flourished in Tang and Song Dynasties, and became closer in Qing Dynasty. At that time, people could not call the emperor or his elders by their first names, otherwise they would be in danger of going to jail or even losing their heads because of taboos. The common taboo method is to change the words to be taboo into other words with the same or similar meaning. As a result, there have been many strange phenomena in the history of China in which names of people, places or things have been changed. For example:
The first month of the lunar calendar was originally called "political month" in ancient times, because the ancient emperor had to accept the sacrifices of civil and military officials in the first month of the year to decide the political affairs of the year. In the Qin Dynasty, because Qin Shihuang was born in January and was named Zheng, the word "Zheng Yue" was changed to "the first month". The word "Zheng" in the first month reads "Zheng", not politics.