Mannix sits next to 5 phonetic neighbors — Magnus, Maddox, and Felix are the closest matches by sound. Most share Mannix's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"son of the monk, son of the devoted one"
"descendant of Bibb, a pet form of Isabel"
"Benevolent; goodwill; one who does good"
"to dazzle, stun with brightness"
"removing darkness through light"
"mild, merciful"
"admirable, worthy of praise"
"elf friend"
"thorn, prickly plant"
"powerful person, dynamic one"
"Modern invented name; energetic and bold spirit"
"spear bearer, warrior"
"of the forest, woodland dweller"
Similar sound: These names share phonetic patterns with Mannix — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Irish Gaelic (Mac Maonach) origins, giving them the same cultural heritage as Mannix.
Rhythm: Mannix is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.