"Cheoseo" (處暑), which means "end of heat," is the fourteenth of the twenty-four seasonal sub-divisions, or solar terms, of the lunar calendar, or the period when the Ecliptic rises to 165° over the horizon.

경기도 여주의 영저포쇄차례

Yeongjeong Poswe Charye in Yeoju City, Gyeonggi-do
Preparing the Portrait and Ritual	Baerye Ceremony	Eumbok

As with the meaning of "Cheoseo," the summer heat ends and the season manifests its course of time from summer to fall. There is a saying that "Autumn comes to the Earth on the back of crickets, and to Heaven over thick clouds." And, as the saying "Past Cheoseo, the mosquito’s mouth gets crooked" implies, the weather cools and even diehard mosquitoes vanish. Around this time, people would visit and tidy up their family graves, and noble men and women would dry out damp books and clothes during the summer, or "Poswe" (曝曬).

성년의 날 행사

"Today Is Cheoseo" in the Chosun Ilbo	"Landscape of Cheoseo" by Lee Eok-yeong

Since the weather around "Cheoseo" attracted much attention, many superstitious proverbs originate from this season. For example, if it rained on "Cheoseo" (known as "Cheoseo rain") grains stored in earthenware would diminish, hence the saying, "From a dozen Cheoseo rains, a multitude of grains are lost," or "When it rains on Cheoseo, the rice in the jar decreases." In other words, to farmers it was only natural that many crops would be lost if it rained on "Cheoseo".