Kylian is the French form of Cillian or Killian, an Irish name of uncertain meaning that is usually linked to ceall, "church", and read as "little church" or "of the church". The French soccer star Kylian Mbappé, World Cup winner in 2018, carried it far beyond France. Kylian was unknown in the United States in 2000, entered the top 1000 in 2021, peaked at number 346 in 2023 right after Mbappé's hat trick in the World Cup final, and ranks number 624 in 2025.