| Tad | Poet, Courageous, Large Hearted | Boy | Gaelic |
| Tallula | Princess of abundance | Girl | Gaelic |
| Tara | Star, Hill | Girl | Gaelic |
| Teague | Poet | Boy | Gaelic |
| Teasag | God is gracious | Girl | Gaelic |
| Teigue | Poet | Boy | Gaelic |
| Terence | Instigator, Rub, Turn, Twist | Boy | Gaelic |
| Terrance | Instigator, Rub, Turn, Twist | Boy | Gaelic |
| Terrence | Instigator, Rub, Turn, Twist | Boy | Gaelic |
| Tiarnach | Lord | Boy | Gaelic |
| Tiarnan | Little Lord | Boy | Gaelic |
| Tiernan | Little Lord | Boy | Gaelic |
| Tierney | Lord | Boy | Gaelic |
| Toal | Ruler of the people | Boy | Gaelic |
| Turlough | Instigator, Rub, Turn, Twist | Boy | Gaelic |
| Ulick | Will Helmet, Protect | Boy | Gaelic |
| Ultan | Of Ulster | Boy | Gaelic |
| Una | Famine, Hunger | Girl | Gaelic |