| tridimensionale | three-dimensional |
| Triduo Pasquale | Easter Triduum |
| triedrico | trihedral |
| triedro | trihedron |
| Triefenstein | Triefenstein |
| Triengen | Triengen |
| triennale | triennial |
| Triente | Triens |
| Trier | Trier |
| Triesen | Triesen |
| Triesenberg | Triesenberg |
| Trieste | Trieste |
| trifase | three phase |
| Trifenilfosfina | Triphenylphosphine |
| Trifenilmetano | Triphenylmethane |
| trifoglio | shamrock |
| Trifola | Tuber |
| Trifolium | Clover |
| Trifolium pratense | Trifolium pratense |
| triforcuto | three-pronged |
| triforio | triforium |
| Triforza | Triforce |
| trifosfato | triphosphate |
| Triftern | Triftern |
| trigemini | triplets |
| Trigenerazione | Trigeneration |
| Trigger di Schmitt | Schmitt trigger |
| triglia | red mullet |
| trigliceride | triglyceride |
| trigliceridemia | triglyceridemia |
| Trigonella foenum-graecum | Fenugreek |
| trigono | trigonal |
| Trigonocefalia | Trigonocephaly |
| Trigonoceps occipitalis | White-headed Vulture |
| trigonometria | trigonometry |
| trigonometrico | trigonometric |
| Trigramma | Trigraph |
| triidruro | trihydride |
| Trikala | Trikala Prefecture |
| Trikolonoi | Trikolonoi |
| Trilbardou | Trilbardou |
| trilingue | trilingual |
| trilione | trillion |
| trilionesimo | trillionth |
