Dillan is a distinctive boys' name in United States, ranking #1088 in 2011 with 171 recorded births. This places Dillan in the top 8% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 1998 with 312 births ranking #597. Since 1996, the popularity has decreased by 27.5%. In 2011, approximately 1 in every 11,105 boys born was named Dillan. FALLING Recent data shows the name is currently falling.