| Abbreviation | Definition |
|---|---|
| APA | American Philological Association |
| APA | American Philosophical Association |
| APA | American Pyrotechnics Association |
| APA | Asian Psychological Association |
| APA | Audio Publishers Association |
| APA | Automobile Protection Association |
| APAA | Asian Patent Attorneys Association |
| APAAA | Andhra Pradesh Amateur Athletic Association (India) |
| APAAA | Asian Pacific American Alumni Association |
| APAARI | Asia Pacific Association of Agricultural Research Institutions |
| APAB | Asian Pacific Association for Biomechanics |
| APAB | Association For Performance Art Berlin |
| APAB | Association of Professional Architects of Belize |
| APABA | Asian Pacific American Bar Association |
| APACS | Asia Pacific Association of Catalysis Societies |
| APACS | Association of Program Administrators for CSTEP and STEP |
| APACS | Association of Psychotherapists and Counsellors Singapore |
| APAD | Association of Public Authority Deputies |
| APADS | Association of Pan African Doctoral Scholars |
| APADS | Association Paris Art Deco Society |