Nixon sits next to 4 phonetic neighbors — Dixon, Mason, and Jackson are the closest matches by sound. Most share Nixon's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"son of Nicholas, son of Nick"
"untamed, wild-natured"
"muddy place, ditch"
"long stone settlement"
"the island, island dweller"
"son of the praised one"
"watchful, vigilant (via Casey)"
"little fire"
"brave, bold"
"strong and courageous"
"fifth"
"jet-black, swift"
"little raven"
"youthful, downy-bearded"
"famous spear"
"maker of cases or boxes"
"wolf"
"phonetic invention, modern American creation"
"gentle, tamed"
"wild rose, thorny shrub"
Similar sound: These names share phonetic patterns with Nixon — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have English origins, giving them the same cultural heritage as Nixon.
Rhythm: Nixon is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.