| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Fionntan | - | Irish, Scottish | ||
| Fionnuala | - | Irish, Irish Mythology | ||
| Fionola | - | Irish, Scottish | ||
| FlaithrÍ | - | Irish | ||
| Flann | FLAN | Irish | ||
| FlannÁN | - | Irish | ||
| Florry | - | Irish | ||
| Flurry | - | Irish | ||
| Galchobhar | - | Ancient Irish | ||
| Gallagher | GAL-ə-gər | Irish, English (Rare) | ||
| Gallchobhar | - | Irish (Rare) | ||
| GarbhÁN | GAHR-vawn | Irish | ||
| Garvan | GAHR-van | Irish | ||
| GearÓId | - | Irish | ||
| Gearalt | - | Irish |