Kassian sits next to 4 phonetic neighbors — Cassian, Cassius, and Caspian are the closest matches by sound. Most share Kassian's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"hollow"
"lord, master"
"hidden store, treasure"
"supplanter"
"new, fresh"
"strength, power"
"from the Roman Gens Terentia"
"son of Hugh"
"modern invented name, sound-based"
"strong, virile, masculine"
"strengthened by God"
"all-knowing, wise"
"of the forest, woodland dweller"
"strong will, brave resolve"
"son of Thomas, son of the twin"
"hairy, rough"
"well-digger"
"defender, advocate"
"powerful ruler, brave leader"
"God has remembered"
"descendant of the champion"
Similar sound: These names share phonetic patterns with Kassian — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Kassian.
Rhythm: Kassian is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.