Lonnie sits next to 4 phonetic neighbors — Ronnie, Connie, and Bonnie are the closest matches by sound. Most share Lonnie's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"ready for battle, noble"
"weary (variant of Leah)"
"stoneworker, mason"
"running water, stream"
"lake (from Welsh lynn)"
"modern American creation"
"devotee of battle rule"
"bowman, one who uses a bow"
"beautiful moon"
"descendant of Raghallach"
"ancestors descendants"
"night, dark beauty (if from Leila)"
"lovely rose"
"labor, work"
"divine gift in its purest form"
"leek settlement, meadow town"
"the cherished one"
"valley waterfall"
"phonetic variant; no inherent lexical meaning"
"she who shall rise again"
Similar sound: These names share phonetic patterns with Lonnie — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Germanic (via Alonzo) origins, giving them the same cultural heritage as Lonnie.
Rhythm: Lonnie is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.