A man at the age of 20 is called a weak crown.
At this time, the coronation ceremony is to put on a hat to show that you are an adult, but you are not strong and young, so it is called "weak". Crown, hat, refers to adulthood. Later generations generally refer to the age of men around 20 years old and cannot be used for women.
It is very particular and cautious to hold the coronation ceremony. First of all, we should choose an auspicious day, choose the guests to be crowned, and prepare the offerings to worship heaven and ancestors. Then, my father and brother will lead us into the ancestral temple to worship heaven and ancestors. The ceremony of coronation lasted from the Zhou Dynasty to the Qing Dynasty, until the late Qing Dynasty and the early Republic of China. As the west wind spread eastward, the crown ceremony gradually declined and disappeared.