Casey sits next to 3 phonetic neighbors — Kasey, Lacey, and Macy are the closest matches by sound. Most share Casey's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"growth, abundance (speculative)"
"son of marsh-dwellers"
"frisky, energetic youth"
"red-haired, ruddy complexion"
"fortunate, good"
"behold, a son"
"fingernail, claw"
"tortoise (alternative Japanese reading)"
"place of elms"
"descendant of Bradán (salmon)"
"strength, manly beauty"
"Frenchman"
"helper, one who helps"
"my God is the Lord, from Elijah"
"honoring God"
"battle"
"strong, healthy"
"clerk, scribe, secretary"
"rich spear, lucky warrior"
"the crowned one"
Similar sound: These names share phonetic patterns with Casey — similar vowel sounds, consonant clusters, or rhythm.
Rhythm: Casey is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.