Marcellus sits next to 4 phonetic neighbors — Marcus, Marcel, and Maximus are the closest matches by sound. Most share Marcellus's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"little warrior, young Mars"
"dweller by the holly"
"well-spoken"
"God is gracious"
"from the marshy plain"
"God supports, Yahweh supports"
"land bordering the sea"
"son of the army ruler"
"from the Egnatius family name"
"church official, rule of law"
"pledge, security deposit"
"high place, elevated land"
"slender and fair"
"jet-black, swift"
"defender, helper of mankind"
"always, at all times"
"from the place Brodie in Moray, Scotland"
"dark settlement"
"man, husband (older Germanic sense)"
"bounty, kindly, beloved"
Similar sound: These names share phonetic patterns with Marcellus — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Marcellus.
Rhythm: Marcellus is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.