Proper noun
Shichi-Go-San
A Japanese rite of passage festival celebrating children at the ages of three, five, and seven years old.
The Shichi-Go-San, the Seven-Five-Three, is a rite of passage for five-year-old boys and three- or seven-year-old girls. Source: Internet
Two such ceremonies are the birth of a child and the Shichi-Go-San. Source: Internet