Declyn is a distinctive boys' name in United States, ranking #4575 in 2025 with 22 recorded births. This places Declyn in the top 33% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2016 with 41 births ranking #2895. In 2025, approximately 1 in every 77,640 boys born was named Declyn. FALLING Recent data shows the name is currently falling.