| CINTA | | - | Indonesian | |
| CINTIA | | THEEN-tyah (Spanish), SEEN-tyah (Latin American Spanish) | Spanish, Hungarian | |
| CINZIA | | - | Italian | |
| CIONAODH | | KIN-eech | Irish | |
| CIPRIAN | | cheep-RYAHN | Romanian | |
| CIPRIANO | | chee-pree-AH-no (Italian) | Italian, Spanish, Portuguese | |
| CIRÍACO | | - | Portuguese, Spanish | |
| CIRCE | | SUR-see (English) | Greek Mythology (Latinized) | |
| CIRIACO | | chee-ree-AH-ko (Italian), thee-ree-AH-ko (Spanish), see-ree-AH-ko (Latin American Spanish) | Italian, Spanish | |
| CIRIL | | - | Slovene | |
| CIRILA | | - | Slovene | |
| CIRILLO | | chee-REEL-lo | Italian | |
| CIRINO | | chee-REE-no (Italian), thee-REE-no (Spanish), see-REE-no (Latin American Spanish) | Italian, Spanish | |
| CIRO | | CHEE-ro (Italian), THEE-ro (Spanish), SEE-ro (Latin American Spanish) | Italian, Spanish | |
| CISSY | | SIS-ee | English | |