Cassidy
Cassidy Name Meaning, Origin & Popularity
/ˈkæs.ɪ.di/
Meaning of Cassidy: Cassidy derives from the Irish surname O'Caiside, meaning "descendant of Caiside." The personal name Caiside is thought to derive from the Old Irish word cas, meaning "curly-haired" or "twisted," though some scholars link it to an older Gaelic root meaning "clever" or "ingenious."
The O'Caiside clan was a prominent bardic family in County Fermanagh, Ulster, historically serving as hereditary poets and historians to the Maguire lords of Fermanagh. That literary and scholarly lineage gives the name a depth that extends beyond its phonetic appeal.
As a feminine given name in the United States, Cassidy gained momentum in the late 1980s and accelerated through the 1990s. It fits within the broader wave of Irish surnames adopted for girls - alongside Kennedy, Riley, and Quinn - that carry an upbeat, slightly tomboyish character.
What Does Cassidy Mean? Origin & Etymology
According to SSA records, Cassidy ranked #476 for girls in the US as of 2024, with 646 births recorded. The name peaked around 2013-2015, when it reached the US top 100, and has since maintained steady mid-rank presence.
Spelling variants Kassidy and Kassidee account for a small fraction of additional SSA registrations. The name remains largely confined to English-speaking countries, with minimal usage in Ireland itself where it functions almost exclusively as a surname.
How Popular Is Cassidy?
Numerology & Symbolism of Cassidy
Based on Pythagorean numerology — a traditional system linking name letters to numbers. Presented for cultural interest.
Cassidy – Similar Names & Alternatives
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Frequently Asked Questions about Cassidy
What does the name Cassidy mean?
The name Cassidy originates in Old Irish Gaelic. Irish names frequently reference natural elements—rivers, landscapes, animals—or carry meanings tied to early Celtic mythology and the warrior tradition of early Irish literature.
How popular is the name Cassidy in the United States?
According to SSA records, Cassidy ranked #476 for girl names in the United States, with 646 births recorded in the most recent annual count. The name hit its highest SSA rank in 2024. It has held a consistent place in US naming statistics across multiple decades.
Where does the name Cassidy come from?
The name Cassidy comes from Irish. It entered English use through the linguistic and cultural channels typical of Irish-origin names—whether through religious texts, migration, or the prestige associated with classical learning. Today it is recognized as a girl’s name across the English-speaking world.