Kayin is a distinctive boys' name in United States, ranking #5877 in 1997 with 10 recorded births. The name reached its all-time peak in 2001 with 31 births ranking #2964. Since 1996, the popularity has decreased by 28.6%. In 1997, approximately 1 in every 188,509 boys born was named Kayin. FALLING Recent data shows the name is currently falling.