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"
"well-spoken, of good repute"
"grace + meadow"
"grace and beloved"
"descendant of Aodh (fire)"
"goddess of wisdom and crafts"
"oak tree (from Ayla)"
"from Tara, Hill of Tara"
"beautiful, fine, delicate"
"descendant of Riagán"
"dream, vision"
"bright, shining light"
"charcoal farm"
"the light"
"good, goodness"
"God is gracious"
"my God is abundance, consecrated to God"
"raven island"
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.