About the Costin surname
The surname Costin has an onomastic interpretation that still needs to be placed in the history of each family line. The form of Costin is compatible with French surname tradition. It may derive from an old given name, a place, a nickname, an occupation, or a regional variant; the historical form of the family line is needed to distinguish between these possibilities. The general meaning of the surname should be distinguished from the history of each family that bears it. The etymological interpretation should be compared with the earliest spellings and places associated with each family line.
Pronunciation:
Kos-tin/kɔstɛ̃/