| Theodotus | | - | Ancient Greek (Latinized) | |
| Theodulus | | - | Ancient Greek (Latinized) | |
| Theophilus | | thee-AHF-ə-ləs (English) | Biblical, Ancient Greek (Latinized) | |
| Theotimus | | - | Ancient Greek (Latinized) | |
| Thucydides | | thoo-SID-ə-deez (English) | Ancient Greek (Latinized) | |
| Timaeus | | tie-MEE-əs (English) | Ancient Greek (Latinized), Biblical Latin, Biblical | |
| Timoteus | | - | Ancient Greek (Latinized) | |
| Tycho | | TIE-ko (English) | Ancient Greek (Latinized) | |
| Xenocrates | | zi-NAH-krə-teez (English) | Ancient Greek (Latinized) | |
| Zeno | | - | Ancient Greek (Latinized), Italian | |
| Zosimus | | - | Ancient Greek (Latinized) | |
| Zoticus | | - | Ancient Greek (Latinized) | |