Caitlyn is a moderately popular girls' name in United States, ranking #118 in 2000 with 2,835 recorded births. The name reached its all-time peak in 1998 with 2,937 births ranking #115. Since 1996, the popularity has increased by 21.5%. In 2000, approximately 1 in every 641 girls born was named Caitlyn. FALLING Recent data shows the name is currently falling.