In cold drink shops, an ice cream with sauce (jam, chocolate sauce, etc.) is called a sundae. It's a transliteration of English sunday. The source of this name is: a city in the United States stipulates that ice cream is not allowed to be sold on sundays. In order to break this rule, a cold drink shop sells an unusual special ice cream on Sundays, that is, ice cream with sauce, and it is called Sunday. Because the name and form are different from ordinary ice cream, the authorities cannot punish it. Had to let it sell. Since then, this cold drink food has been very popular and has been passed down to this day.