Kassidi is a modern spelling of Cassidy, from an Irish surname meaning 'curly-haired.'
Kassidi is a spirited variant of Cassidy, a name that made the journey from Irish surname to given name over the course of the twentieth century. As a family name, Cassidy derives from the Irish Ó Caiside, meaning "descendant of Caiside," and Caiside itself may come from the Irish cas, meaning "curly-haired" — giving the name an appealingly vivid physical origin. The Cassidy clan was historically associated with County Fermanagh in Ulster, and the name carries with it that particular Irish quality of sounding simultaneously ancient and breezy.
The name's transition into the given-name mainstream in the English-speaking world owes something to pop culture — the outlaw Butch Cassidy gave it a dash of frontier romance, and the name appeared in songs, television characters, and children's books across the latter half of the 1900s. By the 1980s and 1990s, Cassidy had become a genuine first-name choice for girls in the United States, drawn by its lively sound and that slightly tomboyish charm that Irish surname-names often carry. The spelling Kassidi takes the name a step further from its Gaelic roots and closer to something phonetically intuitive and visually distinctive.
The double-s and the -i ending give it a modern, energetic look that sets it apart from the standard spelling while preserving the name's essential sound and spirit. It belongs to a family of names — Kassidy, Kassandra, Kassia — where the K-spelling signals a deliberate individuality. For a child named Kassidi, the name promises both personality and a story worth telling: Irish roots, frontier echoes, and a spelling that is entirely her own.