See also the related category hebrew.
Illyn is not popular as a baby name for boys. It is not in the top 1000 names.
Baby names that sound like Illyn include Ilan (Hebrew), Ilim, Ilin, Illin, Ilom, Ilon, Ilym, Elan (English, Hebrew, and Welsh), Elann, Eleim, Elim, Elnee, Elney, Elni, Elnie, Elny, Ilani (Hebrew), Elimoo, Ielemia, and Elne.
† approx English pronunciation for Illyn: IH as in "it (IH.T)" ; L as in "lay (L.EY)" ; N as in "knee (N.IY)"