Kiernan is a distinctive boys' name in United States, ranking #2823 in 2018 with 43 recorded births. The name reached its all-time peak in 2008 with 77 births ranking #1888. Since 1996, the popularity has decreased by 14.0%. In 2018, approximately 1 in every 42,220 boys born was named Kiernan. RISING Recent data shows the name is currently rising.