Kayleen is a modern American blend of Kay, the short form of Katherine, with the -leen ending of Kathleen and Colleen; Katherine goes back to the Greek katharos and means "pure", while Kathleen's ending comes from the Irish Caitlín. The name can also be read as a spelling of Kaylin. Kayleen stood at number 1321 in 2000, spent 2009 and 2010 in the top 1000 with a peak at number 916 and ranks number 2524 among girls' names in 2025.