Thayer sits next to 3 phonetic neighbors — Thatcher, Slater, and Draper are the closest matches by sound. Most share Thayer's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"army of the people, warrior of the nation"
"counsel, chief"
"resolute will, helmet of will"
"the sky, royalty"
"warrior's settlement, warrior's town"
"strong, valiant"
"joyful celebration, festivity"
"thunder, god of thunder"
"chalice, cup"
"noble, distinguished"
"son of Jay, supplanter"
"one who resembles God"
"three, third"
"bear strength"
"son of one with a bright mind"
"healer"
"dignity, nobility"
"Eorla's settlement (personal name etymology)"
"griffin-like (legendary creature)"
"church, monastic cell"
"from Dreux (ancient French city name)"
Similar sound: These names share phonetic patterns with Thayer — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old German theod + hari origins, giving them the same cultural heritage as Thayer.
Rhythm: Thayer is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.