Cassidy is a distinctive boys' name in United States, ranking #2494 in 2001 with 39 recorded births. The name reached its all-time peak in 1996 with 78 births ranking #1371. Since 1996, the popularity has decreased by 50.0%. In 2001, approximately 1 in every 49,816 boys born was named Cassidy. STABLE Recent data shows the name is currently stable.