Rhianon is a distinctive girls' name in United States, ranking #7939 in 2000 with 13 recorded births. The name reached its all-time peak in 1998 with 14 births ranking #7012. Since 1996, the popularity has increased by 85.7%. In 2000, approximately 1 in every 139,690 girls born was named Rhianon. FALLING Recent data shows the name is currently falling.