| # | Name | Origin | Meaning | Gender | |
|---|---|---|---|---|---|
| 661 | Fogarty | Irish | Exiled. | M | |
| 662 | Fogerty | Irish | Exiled. | M | |
| 663 | Foley | Irish | Plunders. | M | |
| 664 | Forba | Irish | Owns the fields. | M | |
| 665 | Forgael | Irish | Variant of Fergal: Brave. | M | |
| 666 | Ga!l | Irish | Rooster. | M | |
| 667 | Gadhra | Irish | Mastiff. | M | |
| 668 | Gael | Irish | Stranger. | M | |
| 669 | Gaffney | Irish | Calf. | M | |
| 670 | Gaile | Irish | Stranger. | M | |
| 671 | Gairbith | Irish | Rough peace. | M | |
| 672 | Gale | Irish | Stranger. | M | |
| 673 | Gallagher | Irish | Surname. | M | |
| 674 | Galvin | Irish | Sparrow. | M | |
| 675 | Gannon | Irish | Fair. | M | |
| 676 | Gara | Irish | Mastiff. | M | |
| 677 | Garbhan | Irish | Rough. | M | |
| 678 | Garran | Irish | Guards; guardian. | M | |
| 679 | Garret | Irish | Hard or bold spear. An Irish variant of the German Gerard, based on medieval pronunciation. Famous bearer: Irish statesman Garret FitzGerald. | M | |
| 680 | Garrity | Irish | Surname. | M | |