| Acronym | Meaning |
| TGL | Tagalog Language (ISO 639-2 Code) |
| TGO | Togo (ISO 3166 Trigram) |
| TGT | Target |
| TGV | Tanjong Golden Village - Test Generation With Verification - Train ? Grande Vitesse (French For High-Speed Train) |
| TH | Terahenry - Thailand (ISO 3166 And FIPS 10-4 Country Code Digram) |
| TH | Thai Language (ISO 639-1 Code) |
| TH | Thorium |
| THA | Thai Language (ISO 639-2 Code) |
| THA | Thailand (ISO 3166 Trigram) |
| THAAD | Theatre High Altitude Area Defence |
| THAW | Tony Hawk's American Wasteland |
| THB | Thai Baht (ISO 4217 Currency Code) |
| THEGENTRY | The High-End Group Of Earth's New Technologies Research Yield |
| THEL | Tactical High Energy Laser ACTD |
| THG | Tetrahydrogestrinone |
| THUG | Tony Hawk's Underground |
| TI | Tajikistan (FIPS 10-4 Country Code) -Thermal Imaging - Threat Identification - Training Instructor |
| TI | Tebi - Titanium |
| TI | Tigrinya Language (ISO 639-1 Code) |
| TIA | Total Information Awareness Initiative |
| TIBS | Tactical Information Broadcast System |
| TIC | Troops In Contact |
| TID | Target Identification -ter In Die (Latin |
| TIGER | Topologically Integrated Geographic Encoding And Referencing System |
| TIM | Technical Information Memorandum - Technical Interchange Meeting - Toxic Industrial Material - Telecom Italia Mobile |
| TIMS | Tactical Internet Management System - The Institute Of Management Sciences - The International Molinological Society - Thermal Infrared Multispectral Scanner - Thermal Ionization Mass Spectrometry - Travel Information Management Services - Tuberculosis In |
| TINY | That Is |
| TIP | Thermal Identification Panel |
| TIR | Tigrinya Language (ISO 639-2 Code) |
| TIVP | Totally Innocent Victim Of A Party |
| TJ | Tajikistan (ISO 3166 Digram) - Terajoule |
| TJD | Truncated Julian Day |
| TJK | Tajikistan (ISO 3166 Trigram) |
| TJS | Tajik Somoni (ISO 4217 Currency Code) |
| TK | Terakelvin - Tokelau (ISO 3166 Digram) |
| TK | Turkmen Language (ISO 639-1 Code) |
| TKL | Tokelau (ISO 3166 Trigram) |
| TKM | Turkmenistan (ISO 3166 Trigram) |
| TL | Team Leader -Teralitre - Timor-Leste (ISO 3166 Digram) -ThermoLuminescence |
| TL | Tagalog Language (ISO 639-1 Code) |
| TL | Thallium |
| TLA | Three-Letter Abbreviation/Acronym |
| TLAM | Tomahawk Land Attack Missile |
| TLAR | That Looks About Right (chat Shorthand) - Transporter-Launcher And Radar |
| TLATOJL | The Life And Times Of Juniper Lee |
| TLC | Tender Loving Care - The Learning Channel - Thin LayerChromatography-T-Boz Lefteye Chilli |
| TLD | Thermoluminescent Dosimeter - Top-Level Domain |
| TLM | Traditional Latin Mass Or Tridentine Latin Mass |
| TLS | Timor-Leste (ISO 3166 Trigram) -Times Literary Supplement |
| TM | Technical Manual - Theatre Missile - Thematic Mapper -trademark (often Written In Small Superscript Type: TM Or ?) -Turing Machine -Turkmenistan (ISO 3166 Digram) |