Kaj sits next to 4 phonetic neighbors — Kai, Ky, and Guy are the closest matches by sound. Most share Kaj's German-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"to rejoice"
"severe, strict"
"elf army (alternative theory)"
"brave, bold counsel"
"famous throughout the land"
"rhyme seller, poet"
"beautiful name"
"gift of God"
"tailor, one who cuts cloth"
"ridge meadow"
"thatcher, roofer"
"always ruler"
"bear"
"son of Erik"
"divine protection"
"urbane, sophisticated"
Similar sound: These names share phonetic patterns with Kaj — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin (Caius/Gaius) origins, giving them the same cultural heritage as Kaj.
Rhythm: Kaj is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.