Kai

Kai is a name with multiple independent origins across several cultures. In Hawaiian, it means sea, while in Japanese it carries meanings including shell, restoration, or ocean depending on the written character. In Welsh and Arthurian tradition, it derives from the Latin Caius, a Roman clan name of uncertain but possibly Etruscan origin, and appears as the knight Sir Kay in Arthurian legend. Related forms include Kay, Cai, Kye, and the Scandinavian Kaj, where the name is also popular as a short form of names containing the Old Norse element meaning earth.