Halsey sits next to 3 phonetic neighbors — Chelsea, Kelsey, and Lindsey are the closest matches by sound. Most share Halsey's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"hazel island"
"God is gracious (via Jane/John)"
"descendant of Conn (intelligence, chief)"
"chief, noble one"
"hour; now"
"lily flower"
"help, strength"
"noble elf ruler"
"pale purple flower"
"of noble kind"
"rosy, heathen"
"dew of the sea"
"from the mahogany grove"
"bright light"
"high, noble, strong"
"inspired by Impressionist painter Claude Monet"
"from Nimes (city in France)"
"of noble character (from aethel)"
"snow"
"noble, of noble kind"
Similar sound: These names share phonetic patterns with Halsey — 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 Halsey.
Rhythm: Halsey is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.