| Acronym | Meaning |
| TBC | To Be Confirmed |
| TBD | To Be Determined |
| TBGRI | Tropical Botanic Garden And Research Institute (India) |
| TBM | Tactical Ballistic Missile - Theatre Ballistic Missile |
| TBT | Tributyltin |
| TC | Technetium |
| TC | Teracoulomb - Turks And Caicos (ISO 3166 Digram) - United Arab Emirates (FIPS 10-4 Country Code; From Trucial Coast States) |
| TCA | Transformational Communications Architecture -Turks And Caicos (ISO 3166 Trigram) |
| TCAA | Top Counter-Assault Agents |
| TCAS | Traffic Collision Avoidance System |
| TCCCS | Tactical Command |
| TCD | Chad (ISO 3166 Trigram) |
| TCG | Trusted Computing Group - Trkiye Cumhuriyeti Gemisi |
| TCHD | Truck Cargo Heavy Duty |
| TCL | Tool Command Language |
| TCP | Traffic Control Point - Transmission Control Protocol - Trichlorophenol |
| TCU | Texas Christian University |
| TCWMS | Tele-Center Workforce Management System |
| TD | Toon Disney |
| TDA | The Disney Afternoon |
| TDL | Tactical Data Link |
| TDM | Time-Division Multiplexing |
| TDMA | Time Division Multiple Access |
| TDP | Technology Demonstration Programme |
| TDRS | Tracking Data And Relay Satellite |
| TE | Tactical Exploitation -Testosterone To Epitestosterone Ratio -Tight End (football) |
| TE | Tellurium |
| TE | Telugu Language (ISO 639-1 Code) |
| TEAL | Tasman Empire Airways Limited |
| TEAM | Together Everyone Achieves More |
| TED | Technology Entertainment Design Prize |
| TEETH | Tried Everything Else |
| TEL | Transporter |
| TEL | Telugu Language (ISO 639-2 Code) |
| TELAR | Transporter |
| TEMO | Training |
| TENCAP | Tactical Exploitation Of National Capabilities |
| TERS | Tactical Event Reporting System |
| TES | Tactical Event System |
| TEST | Thesaurus Of Engineering And Scientific Terms |
| TEVES | Tensor Vector Scalar Theory |
| TF | French Southern Territories (ISO 3166 Digram) -Task Force -Terafarad |
| TFMPP | Trifluorophenylmethylpiperazine |
| TFR | Total Fertility Rate |
| TFT | Thin-Film Transistor |
| TG | Tajik Language (ISO 639-1 Code) |
| TG | Teragram |
| TG | Togo (ISO 3166 Digram) |
| TGIF | Thank God It's Friday |
| TGK | Tajik Language (ISO 639-2 Code) |