Cathay "Pratica della mercatura", a guide about trade in China, a country he called "Cathay", noting the size of Khanbaliq (modern Beijing) and how merchants could exchange silver for Chinese paper money that could be used to buy luxury items such as silk. Words related to Khitay are still used in many Turkic and Slavic languages to refer to China. However, its use by Turkic speakers within China, such as the Uyghurs, is considered pejorative by the Chinese authority who had tried to ban it. As European and Arab travelers started reaching the Mongol Empire, they described the Mongol-controlled Northern China
Đại Cathay Đại Cathay Đại Cathay, whose real name was Lê Văn Đại was a notorious 1960s Saigon mobster, and was considered as the top or “number one” of the “Four Great Kings” of Saigon's criminal underworld before 1975. The Four Great Kings of the Saigon criminal underworld at the time referred to the four most powerful mobsters in the city, immortalized by the saying: 1st) Đại Cathay, 2nd) Huỳnh Tỳ, 3rd) Ngô Văn Cái, 4th) Ba Thế. Dai Cathay was born in 1940 as the son of Lê Văn Cự, who was a gangster in the market area of Cầu Muối.