When does the cold winter start at nine o'clock?

This means that the time is counted from the winter solstice. The first nine days were 19. The second nine days is 29 and so on. If you count nine nines, that is, 81 days, winter will be over.

The origin of the number nine:

"Jiujiu", also known as Winter Jiujiu, is a popular solar term in China. The "number nine" begins with the "winter solstice" in the 24 solar terms of the lunar calendar every year. This custom was recorded in the Southern and Northern Dynasties.

"Liang Chao Shu Jing Chu Chun Qiu" records: "The winter solstice is 998 1 day, which is the end of cold." Count nine cold days, that is, from the solstice of winter, count a "nine" every nine days until the "99" of 81 days, and the weather will warm up.

In the traditional culture of Han nationality, nine is the extreme number, which is the largest, largest and longest concept. Nine nines is eighty-one, which is the "maximum" number. Ancient Han people thought that September 8 1 day must be the spring after the winter solstice.