Eirian sits next to 5 phonetic neighbors — Arian, Kieran, and Orion are the closest matches by sound. Most share Eirian's Welsh cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"silver, bright, shining"
"from the southern lands"
"bold warrior, warrior chief"
"invented name (no traditional meaning)"
"God is gracious"
"hawk, falcon"
"red king"
"handsome, beautiful"
"home ruler, powerful"
"revered king"
"son of Rawlin, son of Ralph"
"Shade or darkness cast by an object blocking light"
"bright town"
"Craftsman; skilled tradesperson"
"raven warrior"
"He whom Yahweh remembered"
"black-haired"
"fortunate, prosperous"
Similar sound: These names share phonetic patterns with Eirian — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Welsh arian (silver) origins, giving them the same cultural heritage as Eirian.
Rhythm: Eirian is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.