Alethea sits next to 3 phonetic neighbors — Althea, Alethia, and Aletha are the closest matches by sound. Most share Alethea's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"truth"
"surname place name"
"flowing river"
"God is gracious"
"weary, delicate"
"fair of face (alternate Scottish interpretation)"
"white peace, fair and blessed"
"fruitful, she who will rise again"
"evening star"
"eagle meadow"
"image, likeness"
"divine, heavenly"
"gift of God"
"grace, favor from God"
"gift of God"
"olive, peace"
"fair, lovely"
"gift of God (short form of Dorothy/Theodora)"
"free woman, free person"
Similar sound: These names share phonetic patterns with Alethea — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek origins, giving them the same cultural heritage as Alethea.
Rhythm: Alethea is a 4-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.