Male first name (English): Kai; Unknown (Arthurian legend), in the Arthurian legend is Cei (or Kay Kay or Kay), one of the knights of the Round Table on the origin of the name is unclear, perhaps Celtic / Welsh, perhaps derived from Latin name 'Caius' Male first name (German, Low German): Kai, Old High (Word format); origin uncertain clarified, possibly a Frisian children's linguistic shorthand of 'Gerhard', in Germany with the same variants Kai / Kaj / Kay / Cay, but on the other origin, as a female name in use Female first name (German): Kai, Old High (became independent short), origin not known certainly, possibly one of the Scandinavian countries adopted from the short form of 'Katharina', in Germany with the same variants Kai / Kaj / Kay / Cay, but other sources, as a male name in use
