Montserrat sits next to 2 phonetic neighbors — Monserrat and Serrat are the closest matches by sound. Most share Montserrat's Spanish-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"serrated, jagged mountain"
"beloved, variant of Maria"
"bright, visible"
"little Ann, beloved Ann"
"star"
"youthful, descendant of Julius"
"foundation, solid"
"lily flower"
"pearl"
"she who is a rainbow"
"beloved"
"the blue princess (fictional)"
"sea of bitterness (via Mary/Myra)"
"bright, shining one"
"pious, devout"
"noble, of the patrician class"
"jagged mountain"
"of noble kind"
"pure, holy, chaste"
Similar sound: These names share phonetic patterns with Montserrat — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Catalan/Latin origins, giving them the same cultural heritage as Montserrat.
Rhythm: Montserrat is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.