Cassy is a distinctive girls' name in United States, ranking #12391 in 2011 with 8 recorded births. The name reached its all-time peak in 1998 with 50 births ranking #2700. Since 1996, the popularity has decreased by 80.5%. In 2011, approximately 1 in every 219,851 girls born was named Cassy. FALLING Recent data shows the name is currently falling.