Arco sits next to 4 phonetic neighbors — Marco, Arko, and Argo are the closest matches by sound. Most share Arco's Italian-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"Arc; bow; arch - from Latin arcus meaning bow or arch. In music, arco means to play with the bow"
"sacred mountain"
"happy, fortunate, blessed"
"to help, to save, to rescue"
"dweller at the wood"
"prosperous, equal in rank"
"gold, golden one"
"valley dweller"
"bear"
"to spin; to whirl; wild"
"work and power"
"Bright light, torch, shining one"
"famous warrior (from Louis/Ludwig)"
"growing, increasing, flourishing"
"God is gracious"
Similar sound: These names share phonetic patterns with Arco — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Arco.
Rhythm: Arco is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.