| Abbreviation | Definition |
|---|---|
| ACPC | Air Carriers Purchasing Conference |
| ACPP | Airline Cadet Pilot Programme |
| ACPT | Advisory Committee for Pinellas Transportation |
| ACR | Automatic Compression Release |
| ACR | Automotive Collision Repair |
| ACRN | Australian City And Regional Network |
| ACRO | Aircraft Crashes Record Office |
| ACS | Automatic Cab Signal |
| ACSSP | Air Carrier Standard Security Programs |
| ACSV | Armoured Combat Support Vehicle |
| ACT | Adoption Care Transportation |
| ACT | Advanced Clean Transportation |
| ACT | Alternative Commute Transportation |
| ACT | Association for Commuter Transportation |
| ACTC | Amador County Transportation Commission |
| ACTF | Aeronautical Charting Task Force |
| ACTION | Accessible Community Transportation In Our Nation |
| ACTransit | Alameda-Contra Costa Transit |
| ACTS | American Coalition for Traffic Safety, Inc. |
| ACTS | Area Comprehensive Transportation Study |