Kiernan is a distinctive girls' name in United States, ranking #7580 in 2013 with 16 recorded births. The name reached its all-time peak in 2002 with 34 births ranking #3851. Since 1996, the popularity has decreased by 27.3%. In 2013, approximately 1 in every 109,651 girls born was named Kiernan. FALLING Recent data shows the name is currently falling.