Dylan sits next to 4 phonetic neighbors — Dillon, Declan, and Desmond are the closest matches by sound. Most share Dylan's Welsh cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"son of the sea"
"soldier, warrior"
"youthful, downy-bearded"
"divine messenger, heavenly being"
"bear-king, bear-man"
"healer"
"son of Madoc"
"triumph, victory"
"son of the beloved one"
"modern coined name"
"rowan tree (mountain ash)"
"salvation of God, the Lord saves"
"Italian form of John, gift of God"
"protector of people"
"exalted father"
"battle"
"fiery, warm"
"descendant of Bradán (salmon)"
"divine strength"
"universal, whole"
"crooked, enclosed valley"
Similar sound: These names share phonetic patterns with Dylan — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Welsh mythology origins, giving them the same cultural heritage as Dylan.
Rhythm: Dylan is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.