Jillyan is a distinctive girls' name in United States, ranking #8313 in 2008 with 15 recorded births. The name reached its all-time peak in 1999 with 17 births ranking #6035. Since 1996, the popularity has increased by 114.3%. In 2008, approximately 1 in every 126,048 girls born was named Jillyan. FALLING Recent data shows the name is currently falling.