Kiernan is a distinctive girls' name in United States, ranking #5253 in 2017 with 25 recorded births. The name reached its all-time peak in 2002 with 34 births ranking #3851. Since 1996, the popularity has increased by 13.6%. In 2017, approximately 1 in every 69,035 girls born was named Kiernan. FALLING Recent data shows the name is currently falling.