Sidney sits next to 4 phonetic neighbors — Sydney, Sidney, and Cydney are the closest matches by sound. Most share Sidney's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"from Saint Denis"
"dear, beloved (associated folk etymology)"
"jet aircraft, speed"
"free man (via Carson)"
"modern blend: bright house, highest point"
"hunter"
"brave lion, lion-hearted"
"of the sea, of the lake"
"God has seen"
"prosperity protector"
"warrior's estate"
"son of Jack"
"modern invented name"
"famous in battle"
"little Aodh (fire deity)"
"soaring vessel, sky wanderer (symbolic)"
"flowing down (from Jordan)"
"staff bearer, wand wielder"
"god of war"
"seeing clearly, sharp-sighted"
"from Dayton"
Similar sound: These names share phonetic patterns with Sidney — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Anglo-Norman French origins, giving them the same cultural heritage as Sidney.
Rhythm: Sidney is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.