Kay sits next to 3 phonetic neighbors — Kai, Cay, and Kae are the closest matches by sound. Most share Kay's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"rejoice; pure"
"strong, firm, enduring"
"nothing (informal)"
"little one, shapely"
"soldier"
"creative elaboration of Quinton/Quentin"
"modern coinage, possibly 'thankful lion'"
"son of Cole (son of Nicholas)"
"dark-haired chieftain"
"broad stone settlement"
"new house"
"Wealthy, prosperous warrior"
"California (place name nickname)"
"archer, warrior of the yew"
"remembered by the Lord"
"downy-bearded, youthful"
"God will add, God increases"
"jasmine flower, protector"
"thorny shrub, wild rose"
"of the faith, religion"
Similar sound: These names share phonetic patterns with Kay — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Kay.
Rhythm: Kay is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.