Variant of Casey, from Irish Gaelic "cathasaigh" meaning "vigilant" or "watchful."
Cayce is an American original — a spelling variation of Casey that manages to feel both antique and quietly modern. Casey itself descends from the Irish Gaelic "Cathasach," meaning "vigilant" or "watchful," and entered English usage through the Irish diaspora of the nineteenth century. The more phonetic spelling Cayce strips the name of its obvious Irish signals and gives it a dusty, frontier quality, evoking the wide-open spaces of the American South and Midwest where creative respellings of traditional names became an art form.
The name's most famous bearer is Edgar Cayce (1877–1945), the Kentucky-born psychic and mystic known as "the Sleeping Prophet." Cayce would enter a self-induced trance and deliver "readings" on medicine, history, and spirituality, amassing followers across the country and founding the Association for Research and Enlightenment in Virginia Beach. His surname-as-given-name appeal grew after his death, as New Age communities kept his legacy alive throughout the latter twentieth century.
William Gibson, in his novel "Pattern Recognition" (2003), gave the name to his protagonist Cayce Pollard — a cool, intuitive brand consultant — cementing the spelling's association with perceptiveness and unconventional thinking. Cayce occupies a space that few names inhabit: it is simultaneously rooted in Irish tradition and thoroughly American, carrying both the watchful quality of its Gaelic ancestor and a hint of the mystical. Parents drawn to it today often appreciate names that feel discovered rather than chosen — names with a quiet backstory that rewards curiosity.