Millan sits next to 4 phonetic neighbors — Milan, Millen, and Dylan are the closest matches by sound. Most share Millan's Spanish-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"dear little one, devotee"
"chief lord, noble leader"
"God has given"
"man of Rome, from Rome"
"noble ruler (combined symbolic meaning of eagle + wolf)"
"little fire, born of fire"
"Yahweh saves"
"renowned king"
"war, strife"
"like a lion, of Leon"
"praised, lauded"
"descendant of Rian"
"given, gift"
"visionary, seer"
"God strengthens, strength of God"
"world ruler"
"small, humble"
"virile, masculine, strong"
"red (from Spanish rojas)"
Similar sound: These names share phonetic patterns with Millan — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Celtic / Latin origins, giving them the same cultural heritage as Millan.
Rhythm: Millan is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.