Dillan is a distinctive boys' name in United States, ranking #742 in 2005 with 272 recorded births. The name reached its all-time peak in 1998 with 312 births ranking #597. Since 1996, the popularity has increased by 15.3%. In 2005, approximately 1 in every 7,342 boys born was named Dillan. FALLING Recent data shows the name is currently falling.