Joslyn is a distinctive girls' name in United States, ranking #789 in 2004 with 323 recorded births. The name reached its all-time peak in 2010 with 461 births ranking #641. Since 1996, the popularity has increased by 66.5%. In 2004, approximately 1 in every 5,685 girls born was named Joslyn. FALLING Recent data shows the name is currently falling.