Arlo sits next to 4 phonetic neighbors — Harlow, Marlo, and Carlo are the closest matches by sound. Most share Arlo's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"fortified hill"
"from Lucania"
"brave as a wild boar"
"red earth, ground"
"fortunate, prosperous"
"Jehovah is my God"
"barrel maker"
"may God strengthen him"
"gift of God"
"of the forest"
"mounted warrior, horseman"
"glorious fighter"
"heart, mind, spirit"
"lake colony, settlement by the pool"
"noble, mighty of God"
"derived from Calvus, bald"
"growth, abundance (speculative)"
"my messenger, my angel"
"son of Grey"
"magic dignity"
"of Mars, warlike"
Similar sound: These names share phonetic patterns with Arlo — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old English origins, giving them the same cultural heritage as Arlo.
Rhythm: Arlo is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.