| Abbreviation | Definition |
|---|---|
| ACPN | Association of Community Pharmacists of Nigeria |
| ACPO | Association of Chief Police Officers |
| ACPU | Association of Clinical Pharmacology Units |
| ACR | American College of Radiology |
| ACR | American College of Rheumatology |
| ACRE | Association of Commercial Real Estate |
| ACRI | Air Conditioning and Refrigeration Institute |
| ACRIN | American College of Radiology Imaging Network |
| ACRP | Association Canadienne des Restaurateurs Professionnels |
| ACRPI | Association of Clinical Research for the Pharmaceutical Industry |
| ACS | American Chemical Society |
| ACS | American College of Surgeons |
| ACS | Australia Computer Society |
| ACSA | Afghan Computer Science Association |
| ACSG | Association canadienne des science g??omatiques (see CIG-ACSG) |
| ACSG | Association canadienne des science géomatiques (see CIG-ACSG) |
| ACSM | American College of Sports Medicine |
| ACSZ | Asociace Ceskych a Slovenskych Zinkoven |
| ACTR | American Club of Therapeutic Radiologists |
| ACUA | Advisory Council on Underwater Archaeology |