Kadarius sits next to 3 phonetic neighbors — Darius, Kadaris, and Arius are the closest matches by sound. Most share Kadarius's Old Persian via Darius-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"he who holds firm the good"
"lion, my lion"
"rhyme seller, poet"
"man of Attica, from Athens"
"illusion, magic"
"gift of God"
"a salute, tribute, honor"
"bright, splendid"
"son of (Celtic prefix) + divine"
"bequest, inheritance"
"wolf by the stream or pool"
"bright navigational star in Orion"
"modern coinage, no historical meaning"
"ruler of the army (via Walter)"
"creative variant of Jamir"
"Lamb of God (religious symbolism)"
"light"
"God is gracious (through Juan/John root)"
"brightness, greatness"
Similar sound: These names share phonetic patterns with Kadarius — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old Persian via Darius origins, giving them the same cultural heritage as Kadarius.
Rhythm: Kadarius is a 4-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.