Rui is a name shared by several cultures: in Portugal and Brazil it is a medieval short form of Rodrigo, "famous ruler", borne by the soccer great Rui Costa; in Japan it is a modern given name written with characters such as "lapis lazuli"; and in Chinese the syllable can mean "auspicious" or sharp. In the United States it rose from number 8951 in 2000 to number 2307 in 2024 and sits at number 2672 in 2025 with 49 boys.