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"
"From the Aramaic 'Toma', meaning twin; borne by the Apostle Thomas"
"God will uplift"
"king's town"
"bright fame"
"defender of the people"
"fortunate, prosperous"
"victory of the people"
"peaceful, gentle"
"messenger of God, divine messenger"
"healer"
"advice, counsel"
"God is my strength"
"ancestor's descendants"
"to carry, to endure"
"joined, attached, united"
"soldier"
"jet black; speed"
"strong, mighty"
"from the brook"
"son of Madoc"
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.