Althea sits next to 4 phonetic neighbors — Alethea, Althea, and Elthea are the closest matches by sound. Most share Althea's Greek-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"healing, wholesome"
"one who lives or works in the forest"
"brave advisor"
"wide, broad"
"meadow by the bow or bend"
"great, venerable"
"faithful, true, honest"
"Free man; from Germanic karl meaning man or free man, via Old Frenc..."
"surname of English origin, possibly place or occupational"
"hill, mound, burial tumulus"
"possibly from Darius meaning good, kingly"
"hill of the people"
"Courteous, polite, of the court"
"hard, earnest + friend"
Similar sound: These names share phonetic patterns with Althea — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek althainein origins, giving them the same cultural heritage as Althea.
Rhythm: Althea is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.