Jonathan sits next to 3 phonetic neighbors — Jonathon, Nathaniel, and Jonah are the closest matches by sound. Most share Jonathan's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"God has given"
"mild, peaceful"
"the river Jordan"
"gracious, mild"
"descendant of Bradán (salmon)"
"mountain of strength; exalted"
"light, luminous"
"glorious fighter"
"bright fame"
"little blessed one"
"blazing iron"
"the Lord saves"
"God will add"
"tall, imposing one"
"heart, mind, spirit"
"young warrior"
"savior"
"the Lord heals"
"wayside land, roadside settlement"
"from the long ridge"
"elf warrior"
Similar sound: These names share phonetic patterns with Jonathan — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew (Yehonatan) origins, giving them the same cultural heritage as Jonathan.
Rhythm: Jonathan is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.