Jasper sits next to 3 phonetic neighbors — Casper, Caspar, and Vesper are the closest matches by sound. Most share Jasper's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"treasurer, keeper of treasure"
"fortified hill"
"unbranded cattle (etymological origin)"
"man from Lucania"
"just, righteous"
"light, bringer of light"
"victory of the people"
"great, magnificent"
"divine present"
"gift of Yahweh"
"lion"
"fire of the Lord"
"belonging to Julius"
"God is salvation, the Lord saves"
"light, bringer of light"
"son of Madoc"
"little fire"
"son of the beloved one"
"strong, mighty"
"ruler of the army"
"patrician, of noble birth"
Similar sound: These names share phonetic patterns with Jasper — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Persian origins, giving them the same cultural heritage as Jasper.
Rhythm: Jasper is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.