Lyndon sits next to 4 phonetic neighbors — Brandon, London, and Landon are the closest matches by sound. Most share Lyndon's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"lime tree hill"
"boundary gate"
"mountain, mountainous region"
"son of Dubhagan (little dark one)"
"sweet-smelling resin"
"to tame, subdue"
"hazel valley dweller"
"marsh dweller"
"descendant of the fair one"
"god's field, divine meadow"
"young wolf"
"handsome one, bright fire"
"creative modern variant of Ashton/Cashton"
"son of Evar; son of the boar"
"talent, colorful"
"son of Adam"
"God is gracious"
"bald, little bald one"
"anointed one"
"pale, holy"
"member of the Kru seafaring people (West Africa)"
Similar sound: These names share phonetic patterns with Lyndon — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old English origins, giving them the same cultural heritage as Lyndon.
Rhythm: Lyndon is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.