Cai sits next to 3 phonetic neighbors — Kai, Kay, and Cay are the closest matches by sound. Most share Cai's Welsh cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"rejoice"
"cool breeze"
"musical harmony; combination of notes"
"told by God"
"from the alder grove"
"protector"
"bright, shining one"
"God has answered with grace (from Eliana origin)"
"Honor, nobility"
"solitary meadow"
"follower of Christ"
"from the meadow land"
"consistent, reliable presence"
"grace, favor"
"smooth stream"
"gracious, favor (via Hannah/Anne)"
"light of the meadow"
"true, truthful"
"from the west field"
"blue, the color of sky and sea"
"joyful singer"
Similar sound: These names share phonetic patterns with Cai — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Welsh origins, giving them the same cultural heritage as Cai.
Rhythm: Cai is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.