Caitelyn is a variant of Caitlin, from Katherine, traditionally interpreted as pure.
Caitelyn is a variant of Caitlin, which itself comes through the Irish form of Katherine and is traditionally interpreted as pure. The name carries a long line of adaptation, moving from Greek and Latin tradition into Irish usage and then into a wide range of modern spellings.
Caitelyn is one of the more ornamental forms in that lineage. What gives Caitelyn its appeal is the way it preserves the familiar Caitlin sound while making the visual shape more elaborate. That added flourish gives the name a contemporary, slightly embellished feel.
It still sounds friendly and approachable, but the spelling makes it feel a little more dressed up. Like many newer variants of classic names, it lives between tradition and trend, which is often where modern favorites are made.