Pilar sits next to 4 phonetic neighbors — Pilar, Cesar, and Omar are the closest matches by sound. Most share Pilar's Spanish-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"pillar, column"
"from Flanders, Flemish person"
"daylight, the day"
"The great; the large"
"noble, nobility"
"little raven"
"the strait, narrow waterway"
"botanical variant name"
"stony forest"
"small, little"
"olive tree; symbol of peace and wisdom"
"flower settlement"
Similar sound: These names share phonetic patterns with Pilar — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin pila origins, giving them the same cultural heritage as Pilar.
Rhythm: Pilar is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.