Morgan sits next to 2 phonetic neighbors — Morgen and Moran are the closest matches by sound. Most share Morgan's Welsh cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"sea-born, born of the sea"
"of the Cassian family (Roman gens)"
"modern American coinage, son of Case"
"comforted by God"
"son of the lion"
"free man"
"dweller near the ridge"
"strength, force"
"pure, innocent, righteous"
"resolute protector's son"
"brave in battle"
"dweller by the woods"
"gift of God, blessed one"
"descendant of Ceallachán"
"administrator of justice"
"birth, nativity"
"he who descends, descent"
"thankful, grateful"
"water, thermal waters (place name)"
"God has given"
Similar sound: These names share phonetic patterns with Morgan — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Welsh origins, giving them the same cultural heritage as Morgan.
Rhythm: Morgan is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.