Cassidey is a distinctive girls' name in United States, ranking #9409 in 1998 with 9 recorded births. The name reached its all-time peak in 2001 with 11 births ranking #8879. Since 1996, the popularity has increased by 50.0%. In 1998, approximately 1 in every 196,321 girls born was named Cassidey. FALLING Recent data shows the name is currently falling.