| Abbreviation | Definition |
|---|---|
| AOM | Association of Ontario Midwives |
| AOPL | Association of Oil Pipe Lines |
| APT | Automatic Positive Thinking" |
| APT | Automatic Positive Thinking™ |
| AQHA | American Quarter Horse Association |
| ARCA | Alberta Roofing Contractors Association |
| ARIG | Airline Revenue Integrity Group |
| ARSO | Asia Region Suzuki Organization |
| ASGT | Advancing Sustainable Global Trade |
| ASHI | American Society of Home Inspectors |
| ASM2 | Alternative Solution Machine |
| ASSC | Association of Scottish Self Caterers |
| ASTA | American Seed Trade Association |
| ASTA | American Spice Trade Association |
| ASVB | Asociation of Silicon Valley Brokers |
| ATAE | Automotive Trade Association Executives |
| ATSSA | Automotive Transportation Service Superintendents' Association |
| AttB | Atelier to the Bone |
| AWCI | Association of the Wall and Ceiling Industry |
| AWI | Architectural Woodwork Institute |