Kellisa, of Celtic origin, is a rare and unique female given name. It is derived from the Irish surname 'O'Cathasaigh', which means 'descendant of Cathasach'. Kellisa was likely intended as a feminine form of this surname, though it has not traditionally been used as such. The name has a strong, modern sound and offers a distinctive alternative to more common names. It has seen some limited usage in English-speaking countries, particularly the United States.
In 1972 alone, there were five newborn girls named Kellisa.