Kiernan is a distinctive boys' name in United States, ranking #2120 in 2004 with 56 recorded births. The name reached its all-time peak in 2008 with 77 births ranking #1888. Since 1996, the popularity has increased by 12.0%. In 2004, approximately 1 in every 35,443 boys born was named Kiernan. RISING Recent data shows the name is currently rising.