Kiernan is a distinctive girls' name in United States, ranking #4719 in 2019 with 29 recorded births. The name reached its all-time peak in 2002 with 34 births ranking #3851. Since 1996, the popularity has increased by 31.8%. In 2019, approximately 1 in every 57,847 girls born was named Kiernan. FALLING Recent data shows the name is currently falling.