Darcy sits next to 4 phonetic neighbors — Percy, Marcy, and Ciarán are the closest matches by sound. Most share Darcy's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"from Arcy (place name)"
"gracious, merciful"
"God has given"
"child born at a prosperous time"
"modern surname-style name"
"rocky settlement"
"vigorous ruler"
"brave in battle (via Casey etymology)"
"courteous, well-bred, polite"
"watchful, alert, vigilant"
"from the city of Troy"
"royal town or manor"
"light, illumination"
"stag's clearing"
"dweller near ash trees"
"joyful, jovial (from the same root)"
"realm of the dead"
"God will add, increase"
"belonging to the Lord"
"bold ruler, chief power"
Similar sound: These names share phonetic patterns with Darcy — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old French origins, giving them the same cultural heritage as Darcy.
Rhythm: Darcy is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.