Mid-Autumn Festival, three day harvest festival (August 15 in lunar calendar)
Etymology
Sino-Korean word from 秋夕, from秋(“autumn”)+ 夕(“evening”), whose meaning is uncertain. There are many theories that try to explain this, one of which suggests that the word 秋夕 (chuseok) originates from the following phrases:
According to the rite throughout three generations, the emperor, in a spring morning, worships the sun, and, in an autumn evening, the moon, thus clearly has difference.
The commentary by Ying Shao reads "The emperor in spring worships the sun, and in autumn the moon, outside the East Gate, worships the sun by the morning, and the moon by the evening."