| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| CÁEl | - | Irish Mythology | ||
| CÉIbhfhionn | - | Irish Mythology | ||
| CÚChulainn | - | Irish Mythology | ||
| Cian | KEE-an, KEEN | Irish, Irish Mythology | ||
| ClÍDna | - | Irish Mythology | ||
| ClÍOdhna | KLEE-u-na | Irish, Irish Mythology | ||
| Conall | - | Irish, Scottish, Irish Mythology | ||
| ConchÚR | - | Irish, Irish Mythology | ||
| Conchobhar | - | Irish, Irish Mythology | ||
| Conlaoch | - | Irish Mythology | ||
| Connla | - | Irish Mythology | ||
| Conor | KAHN-ər (English) | Irish, English, Irish Mythology |