| Thecla | | - | Dutch (Rare), Late Greek (Latinized) | |
| Theda | | - | German | |
| Thekla | | - | German (Rare), Greek (Rare), Late Greek | |
| Thelonius | | - | Various | |
| Thema | | - | Western African, Akan | |
| Themba | | - | Southern African, Zulu | |
| Themistocles | | - | Ancient Greek (Latinized) | |
| Themistokles | | - | Ancient Greek | |
| Theobald | | THEE-ə-bawld (English) | English (Rare), Ancient Germanic | |
| Theocritus | | - | Ancient Greek (Latinized) | |
| Theoderich | | - | Ancient Germanic | |
| Theodoar | | - | Ancient Germanic | |
| Theodoard | | - | Ancient Germanic | |
| Theodor | | - | German, Swedish, Norwegian, Danish, Czech, Romanian | |
| Theodora | | thee-ə-DAWR-ə (English) | English, Greek, Ancient Greek | |