Sam sits next to 4 phonetic neighbors — Cam, Ham, and Tam are the closest matches by sound. Most share Sam's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"name of God"
"river"
"horse friend"
"spear of God (from Oscar)"
"charcoal, dark"
"protector of people"
"sea fortress, sea friend"
"from the River Clyde"
"God is my help, help of God"
"from the roe deer land"
"strong warrior"
"God has heard"
"from Scotland, a Scotsman"
"ardor, enthusiasm, fierceness"
"dove"
"alert, watchful"
"helper, one who helps"
"ash tree settlement"
"fire (from the sun god Aodh)"
"river that swallows all rivers"
"clay settlement, clay worker"
Similar sound: These names share phonetic patterns with Sam — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew origins, giving them the same cultural heritage as Sam.
Rhythm: Sam is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.