Joni sits next to 4 phonetic neighbors — Joanie, Joni, and Jody are the closest matches by sound. Most share Joni's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"God is gracious"
"divine, heavenly"
"born in June; youthful"
"elevated by God (from -ayah suffix)"
"full of happiness"
"purpose, goal"
"blind, Cecilias clan"
"high tower"
"joyful lake"
"opening, to open"
"creative American coinage"
"sky and waterfall pool"
"blooming, to flourish"
"born at dawn, of the light"
"reed clearing, cleared wood"
"brightness, radiance (Scandinavian)"
"most holy, utterly pure"
"from the hunting ground"
"azalea flower"
"royal, majestic"
Similar sound: These names share phonetic patterns with Joni — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew origins, giving them the same cultural heritage as Joni.
Rhythm: Joni is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.