| Abbreviation | Definition |
|---|---|
| ACR | American College of Radiology |
| ACRF | American College of Radiology Foundation |
| ACRH | American College of RHeumatology |
| ACRM | American College of Rehabilitation Medicine |
| ACRO | American College of Radiation Oncology |
| ACS | American College of Sofia |
| ACS | Associated Colleges of the South |
| ACSA | Association for College Student Affairs |
| ACSAT | Asian College of Science & Technology, now simply known as Asian College. |
| ACSAT | Asian College of Science And Technology |
| ACSC | Air Command and Staff College |
| ACSC | Australian Command and Staff College |
| ACSE | Australian College of Skills and Education |
| ACSEP | Advanced College Summer Enrichment Program |
| ACSEP | Australasian College of Sport and Exercise Physicians |
| ACSEP | Australasian College of Sport Exercise Physicians |
| ACSF | Australian College of Sports and Fitness |
| ACSIS | Algonquin College Student Information System |
| ACSM | American College of Sports Medicine |
| ACST | Australian College of Sports Therapy |