Kayin is a distinctive boys' name in United States, ranking #8512 in 2021 with 9 recorded births. The name reached its all-time peak in 2001 with 31 births ranking #2964. Since 1996, the popularity has decreased by 35.7%. In 2021, approximately 1 in every 194,249 boys born was named Kayin. FALLING Recent data shows the name is currently falling.