Hennessy sits next to 4 phonetic neighbors — Kennedy, Tennyson, and Guinevere are the closest matches by sound. Most share Hennessy's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"descendant of Angus"
"very holy (from Welsh Arianrhod variant)"
"consecrated to God"
"tailor, one who cuts cloth"
"from the Afton River"
"beloved, dear"
"place of gathering; sanctuary"
"royalty, high chief (from lani)"
"joyful, full of joy"
"black-haired, dark wisdom"
"exalted, rising, ascending"
"son of Hugh, child of heart and spirit"
"royal forest clearing, Cyneburg's meadow"
"pure, whole, genuine"
"noble and gentle"
"supplanter, one who follows"
"variant of Asia (the continent)"
"lively, spirited"
"heathland, hay valley"
"rye clearing plus lake"
"narrative, tale"
Similar sound: These names share phonetic patterns with Hennessy — 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 Hennessy.
Rhythm: Hennessy is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.