Renn sits next to 4 phonetic neighbors — Ren, Penn, and Ben are the closest matches by sound. Most share Renn's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"counsel, advice"
"from the wooded hollow"
"mythical bird of rebirth and immortality"
"related to Kimani: full of life"
"son of Piers"
"the sun, solar light"
"ford belonging to the king"
"joined, attached"
"eighth, born eighth"
"of America, American"
"son of the sea, great tide"
"woodland clearing"
"song; nightingale"
"vigilant in battle (via Casey/Cathasaigh)"
"black, swarthy"
"man of prayer, full of goodness"
"dear, beloved"
"young goat"
"slender, graceful"
"craftsman, smith"
"Supplanter (from Jacob/Jakob)"
Similar sound: These names share phonetic patterns with Renn — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old English/Germanic origins, giving them the same cultural heritage as Renn.
Rhythm: Renn is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.