| Truth or Consequences, New Mexico | Truth serum | Truth value |
| Truvada | Truxton, Missouri | TRX2 |
| Trygve Haavelmo | Tryngites | Tryngites subruficollis |
| Trypanosoma | Trypanosoma brucei | Trypanosoma evansi |
| Trypanosomatida | Trypanosomatidae | Trypanosomatina |
| Trypsin | Trypsinogen | Tryptamine |
| Trypticase soy agar | Tryptophan | Trương Tấn Sang |
| TS Entertainment | Tsai Ing-wen | Tsakhiagiin Elbegdorj |
| Tsanko Tsvetanov | Tsar Bomba | Tscherskia |
| Tscherskia triton | TSD | Tseng Labs |
| Tsepo Masilela | Tshepiso Molwantwa | Tshepo Motlhabankwe |
| Tshering Dorji | Tsholola Tshinyama | TSI slant |
| Tsinghua University | Tsingy de Bemaraha Strict Nature Reserve | Tsiolkovsky mission |
| Tsiolkovsky rocket equation | Tskhinvali | TSMC |
| Tsotsi | Tsu (social network) | Tsubasa: Reservoir Chronicle |
| Tsuga | Tsuga canadensis | Tsuga caroliniana |
| Tsuga chinensis | Tsuga diversifolia | Tsuga dumosa |
| Tsuga forrestii | Tsuga heterophylla | Tsuga jeffreyi |
| Tsuga mertensiana | Tsuga sieboldii | Tsuga thuja |
| Tsunami | Tsundere | Tsuneo Imahori |
| Tsuneyasu Miyamoto | Tsung-Dao Lee | Tsutomu Hata |
| Tsuyoshi Kitazawa | Tswana language | Tswett |
| TT pistol | TT81 | TTL |
| TTS | Tu Chor Main Sipahi | TU Dresden |
| Tua Forsström | TuAF TFX | Tuğçe Kazaz |
| Tuba Büyüküstün | Tube and clamp scaffold | Tubeless tire |
| Tuber | Tuberaria | Tuberaria guttata |
| Tubercle | Tubercle (rib) | Tuberculosis |
| Tuberculosis cutis orificialis | Tuberculum impar | Tuberosity of the tibia |
| Tuberous receptor | Tubersent | Tubiflorae |
| Tubin, Iran | Tubipora musica | Tubular pinch effect |
| Tubulidentata | Tubulin | Tubulinea |
| Tuckahoe (village), New York | Tucker & Dale vs. Evil | Tuckerman, Arkansas |
| Tucumcari, New Mexico | Tudanca | Tudaran |
| Tudeh Bin | Tudeh Party of Iran | Tudor Arghezi |
| Tudor rose | TUE | Tufal |
| Tufted capuchin | Tugay Kerimoğlu | Tugboat |
| Tughra | Tughrul Tower | Tugtupite |
| Tuguegarao Airport | TUI | Tui na |
| TUIfly | Tuileries Palace | Tujerdi Rural District |
| Tukums | Tul Yek | Tulan |
| Tulare, South Dakota | Tularemia | Tularosa, New Mexico |
| Tulayha | Tulbaghia | Tulbaghia acutiloba |
| Tulbaghia aequinoctialis | Tulbaghia alliacea | Tulbaghia capensis |
| Tulbaghia leucantha | Tulbaghia montana | Tulbaghia transvaalensis |
| Tulbaghia violacea | Tulbaghieae | Tuleh Kola |
| Tulip | Tulip chair | Tulip mania |
| Tulip Revolution | Tulipa | Tulir |
| Tullahoma, Tennessee | Tullio Lanese | Tullio Levi-Civita |
| Tully (village), New York | Tulsidas | Tuluksak, Alaska |
| Tulun, Iran | Tumansky | Tumansky R-11 |
| Tumansky R-25 | Tumansky R-29 | Tumansky RD-9 |
| Tumblr | Tumblr.com | Tumelo Nhlapo |
| Tummal Inscription | Tumor | Tumor necrosis factor-alpha |
| Tumor progression | Tumour virus | Tumulus culture |
| Tumxuk Airport | TUN | TUN (توضيح) |
| Tuna, Iran | Tunable laser | Tunay Torun |
| Tunbridge, Vermont | Tuncay Şanlı | Tundra |
| Tuner (radio) | Tung Choi Street | Tungsten |
| Tungsten carbide | Tungsten dichloride dioxide | Tungsten disilicide |
| Tungsten(III) oxide | Tungsten(IV) oxide | Tungsten(IV) sulfide |
| Tungsten(IV) telluride | Tungsten(V) bromide | Tungsten(V) chloride |
| Tungsten(VI) oxytetrabromide | Tungsten(VI) oxytetrachloride | Tungsten(VI) oxytetrafluoride |
| Tunguska event | Tuni (footballer) | Tunic |
| Tunica intima | Tunica media | Tunica, Mississippi |
| Tunicata | Tunicate | Tuning fork |
| Tuninter Flight 1153 | Tunis | TUNIS |
| Tunis Dauphine | Tunisair | TunisAir Express |
| Tunisavia | Tunis–Carthage International Airport | Tunisia |
| Tunisia Campaign | Tunisia Polytechnic School | Tunisian Air Force |
| Tunisian Civil Aviation and Airports Authority | Tunisian dinar | Tunisian franc |
| Tunisian Internet Agency | Tunisian passport | Tunisian Pirate Party |
| Tunisian Railways | Tunisian Republic | Tunisian rial |
| Tunisian UAVs | Tunisiana | Tunisie |
| Tunisie 21 | Tunisie Telecom | Tunisietelecom |
| Tunku Abdul Rahman | Tunnel | Tunnel boring machine |
| Tunnel cluster | Tunnel Hill, Georgia | Tunnel magnetoresistance |
| Tunnel of Eupalinos | Tunneling protocol | Tunnelton, West Virginia |
| Tununak, Alaska | Tupac Shakur | Tupelo, Mississippi |
| Tuple | Tupolev | Tupolev ANT-14 |
| Tupolev ANT-20 | Tupolev ANT-35 | Tupolev Tu-104 |
| Tupolev Tu-107 | Tupolev Tu-110 | Tupolev Tu-114 |
| Tupolev Tu-12 | Tupolev Tu-121 | Tupolev Tu-123 |
| Tupolev Tu-124 | Tupolev Tu-125 | Tupolev Tu-126 |
| Tupolev Tu-134 | Tupolev Tu-14 | Tupolev Tu-141 |
| Tupolev Tu-142 | Tupolev Tu-143 | Tupolev Tu-144 |
| Tupolev Tu-154 | Tupolev Tu-16 | Tupolev Tu-160 |
| Tupolev Tu-204 | Tupolev Tu-22 | Tupolev Tu-22M |
| Tupolev Tu-28 | Tupolev Tu-334 | Tupolev Tu-4 |
| Tupolev Tu-404 | Tupolev Tu-444 | Tupolev Tu-70 |
| Tupolev Tu-75 | Tupolev Tu-80 | Tupolev Tu-85 |
| Tupolev Tu-91 | Tupolev Tu-95 | Tupolev Tu-98 |
| Tupper Lake (village), New York | Tuqalajiq Tappeh | Turaif Domestic Airport |
| Turan Dursun | Turan, Isfahan | Turan-Shah |
| Turang Tappeh | Turanism | Turbah |
| Turban | Turban effect | Turbellaria |
| Turbidity | Turbine | Turbine blade |
| Turbinella pyrum | Turbo (film) | Turbo chrysostomus |
| Turbo Outrun | Turbo-Union | Turbo-Union RB199 |
| Turbocharger | Turbofan | TurboGrafx-16 |
