13 baby names with a similar sound and feel to Costello.
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"deep sleep"
"little rock, wise protector"
"maiden, girl"
"mistress, lady of the house"
"Beautiful princess"
"from Obdul (place name or personal name)"
"queen"
"immaculate conception, divine beginning"
"peace and reconciliation"
"wet, rain"
"Great nation; of the Maratha people"
"bold in counsel"
"Possibly from Slavic volna meaning wave, or related to free will"