Rhiannon is a Welsh name that goes back to the Celtic Rigantona, "great queen". In the medieval tales of the Mabinogion, Rhiannon is a figure linked to horses and the otherworld, and Fleetwood Mac's 1975 hit Rhiannon, written by Stevie Nicks, introduced her to American radio. The name ranked number 453 in the United States in 2000, its best year in this century, and has drifted to number 1119 in 2025.