Melvin sits next to 3 phonetic neighbors — Kelvin, Elvin, and Marvin are the closest matches by sound. Most share Melvin's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"council friend"
"son of Bron"
"high stronghold, fort on the headland"
"God will uplift (from Jeremy/Jeremiah)"
"son of James"
"untamed, wild-natured"
"farm settlement of Dudda"
"companion, fellow traveler"
"oarsman"
"wayfarer, traveler"
"brave warrior (later folk etymology)"
"son of Nicholas (via Cole)"
"ruler of the people"
"love and goodness"
"little fire"
"sweetheart, dear one"
"defender of men"
"of Ares, warrior-like"
"the twin"
"strength of God"
Similar sound: These names share phonetic patterns with Melvin — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Celtic/Old English origins, giving them the same cultural heritage as Melvin.
Rhythm: Melvin is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.