What does this festival mean?

Season refers to the climate and phenology of a solar term.

The twenty-four solar terms scientifically reveal the changing laws of astronomical phenomena and natural rhythms, skillfully combine astronomy, agriculture, phenology and folk customs, and derive a large number of related seasonal cultures. In some parts of our country, some festivals will be regarded as festivals. The four seasons refer to the ceremonies and festivals in the order of seasons.

Folklore:

Twenty-four solar terms scientifically reveal the laws of astronomical and meteorological changes, skillfully combine astronomy, natural rhythm and folk customs, and derive a large number of related seasonal cultures, which have become an important part of China traditional culture. In order to express the characteristics of time series more accurately, the ancients divided solar terms into four groups according to climate and phenology: divided, arrived, opened and closed.

"Fen" means vernal equinox and autumnal equinox, which is called "dichotomy" in ancient times. "Solstice" is the summer solstice and the winter solstice, which was called "the second solstice" in ancient times. "Open" is beginning of spring and Changxia, "closed" is beginning of autumn and beginning of winter.