Japheth sits next to 4 phonetic neighbors — Jett, Japeth, and Jasper are the closest matches by sound. Most share Japheth's Hebrew-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"beauty"
"fragrant, perfume"
"God has been gracious"
"faithful, true"
"promised land, heaven"
"father of many nations, father of a multitude"
"deliverer, liberator"
"lamp, light"
"to flow down; to descend"
"great lord"
"lion of God"
"vineyard, garden"
"mouth of brass, one who speaks boldly"
"strength of God, God is my strength"
"completed, finished"
"God has remembered"
"favored, blessed"
"dog (loyal companion)"
Similar sound: These names share phonetic patterns with Japheth — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew origins, giving them the same cultural heritage as Japheth.
Rhythm: Japheth is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.