| Abbreviation | Definition |
|---|---|
| ACTT | Air China Training Tool |
| ACTT | Arkansas Cycle Touring and Training |
| ACTT | Assessment Choices Treatment and Transitions |
| ACTU | Actualite |
| ACTU | AIDS Clinical Trial Unit |
| ACTUALIZE | Actualization |
| ACTUALIZE | Actualized |
| ACTUALIZE | actualizing |
| ACTUATE | actuated |
| ACTURAL | Actuarial |
| ACTUV | ASW Continuous Trail Unmanned Vessel |
| ACTV | Achieving Change Through Values |
| ACTV | Azienda del Consorzio Trasporti Veneziano |
| ACTW | Accelerated Colonoscopy Training Week |
| ACTW | Adaptive Context Tree Weighting |
| ACU | Advanced Control Unit |
| ACU | African Christian University |
| ACU | Airman Combat Uniform |
| ACU | Armor Command Unit |
| ACU | Armored Command Units |