In Chinese, Kai (凯) means "victory" or "triumph". In Hawaiian, it means "sea". As a European name, its origin is unclear. It is thought to be a Frisian diminutive of the names Gerhard, Nicolaas, or Cornelis and thus could mean "brave spear" (Gerhard is a Dutch form of Gerard, which comes from the Germanic elements of ger - "spear" and hard - "brave"), "victory of the people" (Nicolaas is the Dutch form of Nicholas, from the Greek Nikolaos (Νικόλαος), from the elements nike (νίκη) - "victory" and laos (λαός) - "people"), or "horn" (Cornelis is the Dutch from of Cornelius, a Roman family name possibly derived from the Latin element cornu - "horn"). As a given name, Kai saw peaks in popularity in both the early 2000s and again around 2010.