Doc sits next to 4 phonetic neighbors — Rock, Dock, and Lock are the closest matches by sound. Most share Doc's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"teacher, learned one"
"night visitor, one who arrives at dawn"
"priest"
"fighter, battle"
"vigilant in battle (from Casey/Cathasach root)"
"son of Ken, son of the bold"
"high place, island"
"that which is yet to come"
"God's friend, divine companion"
"my light, my flame"
"from the Muscogee (Creek) Nation"
"slender, narrow"
"shining, brilliant"
"lion man (from Leander)"
"young wolf"
"mild, gentle"
"bower, canopy of branches"
"from the rocky hill, crag dweller"
"shining, bright"
"modern American creation, strong settlement"
"modern invented name in the -aiden family"
Similar sound: These names share phonetic patterns with Doc — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Doc.
Rhythm: Doc is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.