Cleo sits next to 4 phonetic neighbors — Clio, Leo, and Theo are the closest matches by sound. Most share Cleo's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"glory, fame"
"mill worker, grinder"
"from Ireland, Ireland"
"ruler of the elves"
"exalted, ascending"
"son of the handsome one"
"green gem, the green one"
"divine knowledge, sacred text"
"lioness"
"beautiful"
"star"
"army host, expedition"
"dark red, crimson"
"in the beginning"
"strong, manly, brave"
"rival, eager"
"heaven, the sky"
"purpose, intention"
"of noble birth"
"son of Finlay (surname origin)"
"orchid flower (Cattleya species)"
Similar sound: These names share phonetic patterns with Cleo — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek origins, giving them the same cultural heritage as Cleo.
Rhythm: Cleo is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.