| # | Name | Origin | Meaning | Gender | |
|---|---|---|---|---|---|
| 641 | Clymena | Greek | Mother of Atalanta. | F | |
| 642 | Clymene | Greek | Mother of Atalanta. | F | |
| 643 | Clyte | Greek | A water nymph. | F | |
| 644 | Clytemnestra | Greek | Murdered Agamemnon. | F | |
| 645 | Clytie | Greek | Mythological water nymph who loved the sun god Helios. She was changed into a sunflower and now always turns her face toward the sun. | F | |
| 646 | Cocytus | Greek | River of lamenting. | M | |
| 647 | Coeus | Greek | Father of Leto. | M | |
| 648 | Coireall | Greek | Lordly. | M | |
| 649 | Cole | Greek | People's victory. | M | |
| 650 | Colette | Greek | Feminine form of Nicholas: People's victory. St. Nicholas is the patron saint of children, sailors, and pawnbrokers - Santa Claus is based on this saint. | F | |
| 651 | Colin | Greek | Variant of Nicholas: People's victory. | M | |
| 652 | Colum | Greek | People's victory. | M | |
| 653 | Cora | Greek | From 'kore' meaning girl or maiden. Famous bearers: Persephone used the title Kore. | F | |
| 654 | Coral | Greek | From the coral of the sea. | F | |
| 655 | Coralie | Greek | From the coral of the sea. | F | |
| 656 | Coralin | Greek | From the coral of the sea. | F | |
| 657 | Coralina | Greek | From the coral of the sea. | F | |
| 658 | Coraline | Greek | From the coral of the sea. | F | |
| 659 | Corella | Greek | Maiden. | F | |
| 660 | Coretta | Greek | Maiden. | F | |