Llewellyn is a distinctive boys' name in United States, ranking #10360 in 2003 with 6 recorded births. The name reached its all-time peak in 2025 with 16 births ranking #5749. Since 1996, the popularity has decreased by 14.3%. In 2003, approximately 1 in every 329,212 boys born was named Llewellyn. RISING Recent data shows the name is currently rising.