Bertrand sits next to 4 phonetic neighbors — Bertram, Brant, and Bernard are the closest matches by sound. Most share Bertrand's French-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"bright raven"
"bright raven"
"named for the giant redwood trees"
"rough clearing or rough woodland clearing"
"defender of men"
"rosemary (when short for Rosemary)"
Similar sound: These names share phonetic patterns with Bertrand — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Germanic origins, giving them the same cultural heritage as Bertrand.
Rhythm: Bertrand is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.