Kiernan is a distinctive girls' name in United States, ranking #9826 in 2015 with 11 recorded births. The name reached its all-time peak in 2002 with 34 births ranking #3851. Since 1996, the popularity has decreased by 50.0%. In 2015, approximately 1 in every 162,241 girls born was named Kiernan. FALLING Recent data shows the name is currently falling.