Rhiannan is a distinctive girls' name in United States, ranking #16015 in 2005 with 6 recorded births. This places Rhiannan in the bottom 17% of ranked US girls' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 1998 with 14 births ranking #7011. In 2005, approximately 1 in every 307,950 girls born was named Rhiannan. RISING Recent data shows the name is currently rising.