Macy sits next to 5 phonetic neighbors — Tracy, Lacey, and Casey are the closest matches by sound. Most share Macy's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"from Massy (a place in Normandy)"
Similar sound: These names share phonetic patterns with Macy — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old French/Norman origins, giving them the same cultural heritage as Macy.
Rhythm: Macy is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.