Nikki sits next to 3 phonetic neighbors — Nicki, Nicci, and Nicky are the closest matches by sound. Most share Nikki's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"victory of the people"
"royal forest clearing, Cyneburg's meadow"
"hill meadow, clearing on the hill"
"wished-for child of grace"
"settlement of free men"
"noble, of noble kind"
"white phantom, fair spirit"
"little Margaret"
"banner, standard-bearer"
"variant of Asia (the continent)"
"beautiful, graceful"
"creative American coinage blending lyrical sounds"
"grey land, rocky ground"
"from the gray lands"
"settlement of Ella's people"
"lake, pool"
"courageous, bold"
"royal, regal"
"loyal"
"high clearing in woodland"
Similar sound: These names share phonetic patterns with Nikki — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek Nikolaos origins, giving them the same cultural heritage as Nikki.
Rhythm: Nikki is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.