| Abbreviation | Definition |
|---|---|
| ACNM | Associated Contractors of New Mexico |
| ACNM | Autism Center of North Mississippi |
| ACNS | AIDS Coalition of Nova Scotia |
| ACNT | Augsburg Commentary on the New Testament |
| ACNT | Australian College of Natural Therapies |
| ACNU | Aguman Capampangan Northwest USA |
| ACNU | Asociacion Cubana de las Naciones Unidas |
| ACNUR | Alto Comisionado de las Naciones Unidas para los Refugiados |
| ACO | Active Continuous Optimization |
| ACO | ADHD Coaches Organization |
| ACO | Adolph Casimir Ochs |
| ACO | Algorithms Combinatorics and Optimization |
| ACO | American Composers Orchestra |
| ACO | Announcement of Collaboration Opportunity |
| ACO | Ant Colony Optimization |
| ACO | Atlantic Coast Orthopedic |
| ACO | Attendant Control OpenBus |
| ACOA | Alpaca Coalition of America |
| ACOA | Ant Colony Optimization Algorithms |
| ACOB | Air Carrier Operating Bulletins |