Oona sits next to 3 phonetic neighbors — Una, Luna, and Nona are the closest matches by sound. Most share Oona's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"lamb"
"graceful lily"
"moonlight (from Ayla)"
"fine art, artistry"
"from Tara, Hill of Tara"
"dream, vision"
"clay, earth (Etruscan root)"
"strategic warfare and the arts"
"illusion, magic, divine power"
"little rock, harmony"
"heavenly path, sky fragrance"
"beloved, wished-for child"
"foreign woman (as variant of Barbara)"
"power, elevated"
"gracious gift"
"God is gracious"
"near, close"
"well-spoken, of good repute"
"of the wild, forest creature"
"maiden, daughter"
Similar sound: These names share phonetic patterns with Oona — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old Irish origins, giving them the same cultural heritage as Oona.
Rhythm: Oona is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.