| Acronym | Definition |
|---|
| ATT | Attorney |
| ATT | American Telephone and Telegraph, Inc. (AT&T) |
| ATT | Attention |
| ATT | Attached |
| ATT | All The Time |
| ATT | At This Time |
| ATT | Attic (linguistics) |
| ATT | Attitude |
| ATT | Apprentice(ship) Technical Training |
| ATT | Arms Trade Treaty (UN) |
| ATT | Atentamente (Spanish) |
| ATT | Attenuator |
| ATT | Association of Taxation Technicians (UK) |
| ATT | Automated Test Tools |
| ATT | Authority to Test |
| ATT | About Time Too |
| ATT | Advanced Transportation Technology |
| ATT | Active Torque Transfer |
| ATT | Applecare Technician Training |
| ATT | American Telephone and Telegraph |
| ATT | Advanced Technical Training |
| ATT | Afghan Transit Trade |
| ATT | Attard (postal locality, Malta) |
| ATT | American Tobacco Trail |
| ATT | Air Tightness Testing |
| ATT | Average Talk Time (telemarketing) |
| ATT | Anti-Theft Technology (Intel Corp.) |
| ATT | Authorization to Transport (firearm permit, Canada) |
| ATT | alt.toys.transformers (newsgroup) |
| ATT | African Think Tank (Australia; leadership) |
| ATT | Access to Technologies |
| ATT | Advanced Teaching Techniques |
| ATT | Anti-Torpedo Torpedo |
| ATT | Advanced Transportation Technologies |
| ATT | Assign Terminal Type (US DoD) |
| ATT | Antithrombotic Trialists' |
| ATT | Agents in Traffic and Transportation (Workshop) |
| ATT | Associated Talmud Torahs |
| ATT | Army Training Test |
| ATT | Advanced Theater Transport |
| ATT | Athletic Therapy Today |
| ATT | Anterior Tibial Translation |
| ATT | Advanced Training Technologies |
| ATT | Automatic Target Tracking |
| ATT | Ammonia Tolerance Test |
| ATT | American Top Tools |
| ATT | Advanced Tree Technology (investment timber) |
| ATT | Antitetanus Toxoid (vaccination) |
| ATT | Advanced Transport Technology |
| ATT | Attitude Retention System (aviation) |
| ATT | Automatic Toll Ticketing |
| ATT | Automatic Trunk Testing |
| ATT | Aircraft Total Time (aviation inspection) |
| ATT | Advanced Tank Technologies |
| ATT | Alternative to Transplant (medicine) |
| ATT | Aegis Test Team |
| ATT | Armored Troop Transport |
| ATT | All Thrust Termination |
| ATT | Applied Transmission Technologies |
| ATT | ASEAN Travel and Tours |
| ATT | Automatic Trunk Test (system) |
| ATT | Aerosol Transport Test |
| ATT | Assembly Task Team |
| ATT | Asynchronous Thread Termination |
| ATT | Advanced Technologies and Travel |
| ATT | Advanced Testing Technology |
| ATT | Acoustic Target Tracker |
| ATT | Automatic Turbine Testing |
| ATT | Anaerobic Treatment Technology |
| ATT | Automatic Tank Target |
| ATT | Authorization to Tool |
| ATT | Army Transformation Team |
| ATT | Air Touch-Teletrac |
| ATT | Advanced Tilting Train |