| Theo | Man | Greek Names |
| Theobald | Man | English Names |
| Theodora | Woman | Greek Names |
| Theodore | Man | Greek Names |
| Theodoric | Man | German - Ostrogothic Names |
| Theodorsia | Woman | American Names |
| Theodosia | Woman | Greek Names |
| Theodosius | Man | Greek Names |
| Theodwin | Man | German - Old High German Names |
| Theola | Woman | American Names |
| Theon | Man | Greek Names |
| Theone | Woman | Greek Names |
| Theophanes | Man | Greek Names |
| Theophania | Woman | Greek Names |
| Theophila | Woman | Greek Names |
| Theophilia | Woman | Greek Names |
| Theophilus | Man | Greek Names |
| Theora | Woman | Greek Names |
| Theoren | Unisex | French Names |
| Theoris | Man | Greek Names |