Rhiannon is a distinctive girls' name in United States, ranking #580 in 2003 with 476 recorded births. The name reached its all-time peak in 1999 with 651 births ranking #424. Since 1996, the popularity has increased by 60.3%. In 2003, approximately 1 in every 3,838 girls born was named Rhiannon. STABLE Recent data shows the name is currently stable.