| t | Tonne |
| t. | tief = deep |
| T | Township; photogrammetric elevation (measured with stereo plotter) |
| T. | Tiefe = depth |
| TAC | Terrain Analysis Center (USCE); Technology Accreditation Commission (ABET); Topcon America Corporation |
| TACA | Transportes Aereos Centro Americanos |
| TACAN | Tactical Air Navigation |
| TAG | Tabular and Graphic (system) |
| TAPS | Tennessee Assn. of Professional Surveyors |
| TAR | Tape address register |
| TARGA | TrueVision Advanced Raster Graphics Adapter |
| TASC | Transportation Administration Service Center (US); The Analytic Sciences Corp. |
| TASMAP | Tasmania Dept. of Lands |
| TAVO | Tubinger Atlas des Vorderen Orients |
| TAZ | Traffic analysis zone |
| TBD | To be determined |
| TBM | Temporary bench mark; Tunnel boring machine |
| TBPLS | Texas Board of Professional Land Surveying |
| TBV | To be verified |
| T.C.H. | Thomas Campanius Holm |
| TCI | Touring Club Italiano |
| TCP/IP | Transmission Control Protocol/Internet Protocol |
| TCT | Trans-continental Traverse (U.S.) |
| TD | Thematic data; Topographic Div. (USGS); Total depth |
| TdA | Teledeteccion Aplicada, S.A. |
| TDC | Tennessee Dept. of Conservation |
| TDD | Telecommunications Device for the Deaf |
| TDM | Tasmania Dept. of Mines |
| TDN | Topografische Dienst Nederland |
| TDOA | Time Difference of Arrival |
| TDR | Time Domain Reflectrometry |
| TDRSS | Tracking and Data Relay Satellite System |
| TDS | Tripod Data Systems |
| TDSA | Tribal designated statistical area |
| TDT | Terrestrial Dynamic Time |
| T.E. | Topographical Engineer |
| TEC | The Engineering Center; Topographic Engineering Center (USCE) |
| TEFIS | Transmission Electrical Facilities Information System (Santee Cooper) |
| TEKPLOT | Tektronix Plotting (DLG software) |
| TELEX | Teletypewriter Exchange |
| TELNET | Telecommunications Network |
| Tenn. | Tennessee |
| TERCOM | Terrain Contour Matching |
| TERSS | Tasmanian Earth Resource Satellite Station |
| TES | Terrain Edit System |
| TESC | Tile enclosed elevator with self-closing traps |
| TESEMPS | Terrain Edit Station/Elevation Matrix Processing System |
| Tex. | Texas |
| TEXPLOT | Tektronix Plotting (DLG software) |
| TFC | Forestry Commission Tasmania |
| TFEL | Thin-film electrolumiscent |
| TFH | Technische Fachhoschule (Berlin) |
| TGS | Technicolor Graphic Services, Inc. |
| T.H. | Triple hydrant; Territory of Hawaii |
| THSOA | The Hydrographic Society of America |
| TI | Technical instruction; Technical investigation; Texas Instruments; Topographic instruction |
| TIC | Technical Information Center (NASA) |
| .TIF | Tagged Image File |
| TIFF | Tagged Image File Format |
| TIGA | Texas Instruments Graphics Architecture |
| TIGER | Topologically Integrated Geographic Encoding and Referencing |
| TIGRIS | Topologically Integrated Geographic Resource and Information System |
| TIMS | Therms Infrared Multispectral Scanner |
| TIN | Triangulated irregular network |
| TIRS | Thermal Infrared Scanner |
| TJSA | Tribal jurisdiction statistical area |
| TLI | Terrain Line Interpolation |
| TLID | TIGER/Line Record Identification Number |
| TLM | Telemetry; Topographic Line Map |
| TLSD | Tuvalu Lands and Survey Div. |
| TLUI | Traditional Land Use Inventory (NSB GIS Div.) |
| TLV | Threshold limit value |
| TM | Thematic Mapper (Landsat); Timber management |
| TMAC | Technical Mapping Advisory Council (U.S.) |
| TMC | The Map Collector (journal); Thinking Machines Corp. |
| TMDL | Total maximum daily load |
| TMLS | Ministry of Lands, Survey and Natural Resources (Tonga) |
| TMS | Thematic Mapper Simulator; Topographic Mapping Service (Geomatics Canada); TIGER Mapping Service |
| TN | Tennessee |
| TNP | Transportation Network Profile |
| TNRIS | Texas Natural Resources Information system |
| TNS | TopoNet Server (Maps a la carte, Inc.) |
| T-O | Orbis terrarum (Medieval European map type: Nile and Don rivers and Mediterranean form a "T" surrounded by ocean in the shape of an "O") |
| TOPOCOM | U.S. Army Topographic Command |
| Tp. | Township |
| TPC | Tactical Pilotage Chart |
| TPM | Theodolitprufmachine |
| TPS | Thin-plate splines |
| TQ | Topographic quadrangle |
| TR | Township and Range (public land survey) |
| TRACE | Topographic Resources and Cost Evaluation (system) |
| Trafo | Transformator |
| TRB | Technical Review Board (U.S.) |
| TRF | Terrestrial Reference Frame |
| Trgf. | Tragfahigkeit = Carrying capacity |
| TRI | Toxic Release Inventory (USEPA) |
| T/RS | Township/Range System |
| TRS | Trimble Reference Station |
| TRSC | Thailand Remote Sensing Center |
| TS | Top secret |
| TSA | Texas Surveyors Association |
| TSC1 | Trimble System Controller |
| TSD | Treatment, storage and disposal sites |
| TSGS | Topographic Section, General Staff (Gt. Brit.) |
| TSI | Teqnical Services Inc. |
| TSOP | The Society for Organic Petrology |
| TSPS | Texas Society of Professional Surveyors |
| TSS2 | TurboSurvey Software 2 |
| TT | TT Maps & Publications Private Ltd. |
| TTD | Tactical terrain data |
| TTY | Teletype |
| TUNS | Technical University of Nova Scotia |
| TVA | Tennessee Valley Authority |
| TVP | Topological vector profile |
| TWA | Time-weighted average |
| Twp. | Township |
| TX | Texas |