Arantza is a Basque name taken from Arantzazu, a title of the Virgin Mary venerated at a mountain sanctuary in Gipuzkoa; the Basque word arantza means "thorn" or "hawthorn", and the name recalls the legend of a shepherd who found an image of Mary in a thorn bush. The simplified spelling Aranza is common in Mexico. Arantza was almost unknown in the United States in 2000 at number 15257, peaked at number 1322 in 2014 and stands at number 2904 in 2025 with 58 births.