Kellan is an Irish name, usually traced to Caolán and the Gaelic word caol, so it means "slender" or "narrow"; some also link it to the surname Kelly. The spelling with -an gained ground in the United States in the 2000s alongside Kellen and Keegan. Kellan entered the top 1000 in 2007, peaked at number 364 in 2011 and has drifted down since, landing at number 1031 in 2025.