Terran sits next to 4 phonetic neighbors — Terra, Tara, and Teagan are the closest matches by sound. Most share Terran's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"of the earth, earthling"
"earnest and springlike"
"God is gracious"
"from Airelle, open meadow"
"house of figs"
"God is gracious"
"harvester, reaper"
Similar sound: These names share phonetic patterns with Terran — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Terran.
Rhythm: Terran is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.