Daylan is a modern spelling of Dylan, the Welsh name of a sea god in the Mabinogion, usually explained as "son of the sea" or great tide. The spelling with -ay- came up in the 1990s when Dylan was a top 30 name and parents looked for fresh variants. Daylan ranked number 1420 in 2000, peaked at number 1225 in 2003 and stands at number 2576 in 2025.