Rhiannon is a moderately popular girls' name in England & Wales, ranking #188 in 2006 with 274 recorded births. The name reached its all-time peak in 1998 with 657 births ranking #83. Since 1996, the popularity has decreased by 58.1%. In 2006, approximately 1 in every 1,092 girls born was named Rhiannon. STABLE Recent data shows the name is currently stable.