| Acronym | Definition |
|---|
| ACAS | Advisory, Conciliation and Arbitration Service (UK) |
| ACAS | Assured Compliance Assessment Solution (software; US DoD) |
| ACAS | Airborne Collision Avoidance System |
| ACAS | Automotive Collision Avoidance Systems |
| ACAS | Application Control Architecture Services |
| ACAS | American Capital Strategies, Ltd |
| ACAS | Asymptomatic Carotid Atherosclerosis Study |
| ACAS | Association of Concerned Africa Scholars |
| ACAS | Asian Community AIDS Services |
| ACAS | Associate of the Casualty Actuarial Society |
| ACAS | Aged Care Assessment Service (Australia) |
| ACAS | Aircraft Collision Avoidance System |
| ACAS | Acetyl-Coenzyme A Synthetase (enzyme) |
| ACAS | Arizonans Concerned about Smoking |
| ACAS | Air Collision Avoidance System |
| ACAS | Application Control Architecture Services (DEC) |
| ACAS | Assistant Chief of Air Staff |
| ACAS | Aboriginal Children's Advancement Society |
| ACAS | Acute Community-Acquired Sinusitis (disorder) |
| ACAS | American Correctional Association Standards |
| ACAS | Association for Critical Animal Studies |
| ACAS | Automatic Collision Avoidance System |
| ACAS | Australian Crop Accreditation System |
| ACAS | Afro-Cuban All Stars |
| ACAS | Adherent Cell Analysis and Sorting |
| ACAS | Associate Contracting Assistance Specialist |
| ACAS | Appleton Central Alternative School |
| ACAS | American College of Applied Science (Crescent City, FL) |
| ACAS | Advanced Close Air Support |
| ACAS | Automated Cable Analyzer System |
| ACAS | AUTOVON Central Alarm System |
| ACAS | Alarm Control and Annunciator Station |
| ACAS | Army Commissary Automated System |
| ACAS | Automated Circuit Assurance, Short |
| ACAS | Automated Commissary Accounting System |