Unknown; possibly a modern variation of Caius or Kai.
Kyus is a rare modern name with an unclear etymology. It is likely a creative phonetic spelling or a variation of the Latin name Caius, meaning 'rejoice', or influenced by the Hawaiian name Kai. Its usage in the United States is extremely limited, often chosen for its unique sound and contemporary feel.
Less common today
Kyus isn't in the latest US Top 1000. It last peaked at #5,493 in 2018.
US births per 5-year period, 1990βpresent (SSA data).