Serena sits next to 3 phonetic neighbors — Sienna, Serene, and Selena are the closest matches by sound. Most share Serena's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"tranquil, serene, clear"
"descendant of Riagan"
"grace, favor"
"woodland clearing of the wren"
"creative modern blended form"
"heaven (spelled backwards)"
"each of the two"
"born again"
"of the elm grove"
"dark beauty"
"God is gracious"
"from the town of Brielle"
"famous in battle"
"defender, helper"
"heavenly, of the sky"
"vision of beauty"
"crown, garland"
"noble, resolute"
"red king; red-haired ruler"
"pleasant wood; meadow near a lake"
"oak tree clearing"
Similar sound: These names share phonetic patterns with Serena — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Serena.
Rhythm: Serena is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.