Kayin is a distinctive boys' name in United States, ranking #5074 in 2013 with 18 recorded births. The name reached its all-time peak in 2001 with 31 births ranking #2964. Since 1996, the popularity has increased by 28.6%. In 2013, approximately 1 in every 105,070 boys born was named Kayin. FALLING Recent data shows the name is currently falling.