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"
"brightness, greatness"
"gift, blessing (invented, Zion root)"
"champion, passionate one"
"peaceful power"
"noble, famous"
"beloved friend"
"gift of jasmine"
"one who lives in a valley"
"maile vine (sacred Hawaiian plant)"
"noble and strong, from the sea"
"land of God (via Marrakesh, Berber origin)"
"descendant of Raghallach"
"peace-giver, one who pacifies"
"scribe, one who reads and writes"
"rich, wealthy"
"gift of God (gift of Yahweh)"
"from Laurentum, laurel wreath"
"dear, beloved"
"modern compound: Mc (son of) + Aiden (little fire)"
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.