Kayin is a distinctive boys' name in United States, ranking #4325 in 2012 with 23 recorded births. The name reached its all-time peak in 2001 with 31 births ranking #2964. Since 1996, the popularity has increased by 64.3%. In 2012, approximately 1 in every 82,462 boys born was named Kayin. FALLING Recent data shows the name is currently falling.