The name Cassidy is of Irish origin, derived from the Gaelic surname Ó Caiside, meaning 'curly-headed.' It originated in County Fermanagh, Northern Ireland, and was known for its prominent members in medicine, religion, and the arts. Over time, the name spread globally through emigration, becoming a common surname in the U.S., U.K., Canada, Australia, and New Zealand. The name's importance lies in its rich history and cultural significance, reflecting the heritage of its bearers.
