Cassidey is a distinctive girls' name in United States, ranking #8879 in 2001 with 11 recorded births. The name reached its all-time peak in 2001 with 11 births ranking #8879. Since 1996, the popularity has increased by 83.3%. In 2001, approximately 1 in every 163,687 girls born was named Cassidey. FALLING Recent data shows the name is currently falling.