Rowan sits next to 3 phonetic neighbors — Owen, Roman, and Rowen are the closest matches by sound. Most share Rowan's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"little red-haired one"
"Yahweh has shown favor"
"excellent; unbeatable"
"elf counsel, supernatural wisdom"
"gravelly homestead"
"strong, firm, enduring"
"Yahweh is God"
"supplanter, one who follows at the heel"
"Twin"
"from the coal settlement or dark town"
"strong, mighty"
"son of Carr (marsh dweller)"
"black gemstone; jet"
"son of Hudd"
"Yahweh has been gracious"
"from the hay enclosure"
"son of the sea, great tide"
"woodcutter, carpenter"
"dove"
"venerable, sacred"
"homestead by a stream"
Similar sound: These names share phonetic patterns with Rowan — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Irish Gaelic origins, giving them the same cultural heritage as Rowan.
Rhythm: Rowan is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.