| Abbreviation | Definition |
|---|---|
| ACT | Allied Command Transformation |
| ACT | Analysis Control Team |
| ACT | Australian Capital Territory |
| ACT | Automatic Continuous Tuning |
| ACTCO | Action Code |
| ACTD | A Call To Duty |
| ACTD | Advanced Concept Technology Demonstrator |
| ACTD | Automated Command Training Division |
| ACTE | Advanced Career Transition Education |
| ACTEDS | Army Civilian Training Education and Development Systems |
| ACTEDS | Army Civilian Training Education Development System |
| ACTEDS | Army Civilian Training, Education and Development System |
| ACTF | Army Constructive Training Federation |
| ACTFAST | Advanced Concepts and Technology Frequency Agile Solid-State Tuner |
| ACTFAST | AEGIS COTS Technology Family Analysis and Selection Tool |
| Actg | Acting |
| ACTID | Advanced Concepts Test Integration Directorate |
| ACTII | Advanced Concept and Technology II Program |
| ACTO | Action Officer |
| ACTO | Army Communicative Technology Office |