Cady is an anglicized Irish surname-name, often linked to meanings like "helper" or "descendant of Caid."
Cady functions as a standalone given name with several possible origins. It may derive as a nickname from Cadence — the musical term from Latin cadentia, meaning 'a falling' — or as a shortened form of Arcadia, the classical Greek pastoral paradise. It also echoes the Irish Gaelic surname Mac Caidigh and has been used as an anglicization of various Celtic names.
Like many surname-turned-first-names, Cady carries a breezy informality that belies a rich onomastic history, sitting comfortably alongside Sadie, Hadley, and Brady in the American informal-name tradition. The name's most historically significant bearer is Elizabeth Cady Stanton (1815–1902), the American suffragist and social activist who co-organized the Seneca Falls Convention of 1848 — the first women's rights convention in American history — and co-authored the Declaration of Sentiments. Her middle name Cady, inherited from her mother's family surname, gave the name a strong association with feminist intellectual history long before it became a standalone given name.
In using it as a first name, 19th and early 20th-century families were paying tribute to her legacy. In contemporary culture, Cady received a significant pop-culture boost from the 2004 film 'Mean Girls,' in which Lindsay Lohan plays Cady Heron, a homeschooled teenager navigating the social hierarchies of an American high school. The character's name — spelled with that distinctive 'C' — introduced the spelling to a generation of viewers and contributed to the name's quiet rise in baby naming data through the 2000s and 2010s. Today it reads as crisp, unpretentious, and subtly literary.