"Blend of Addie and Lynn"
The name Addilyn is commonly a female name from the "American" origin.
Addilyn is a modern American formation that joins the diminutive Addie, familiar from names such as Adeline and Addison, to the suffix Lynn. The written form divides cleanly as Addi plus lyn, and the name first appears in United States birth records in 1999, which places its coinage in the period when -lyn endings were being attached to existing name elements in American naming. It is not an inherited name with a recorded meaning in an older language.
The pronunciation of Addilyn is AD-ih-lin.