| Abbreviation | Definition |
|---|---|
| ABLE | Association for Biology Laboratory Education |
| ABM | Assured British Meat |
| ABO | Air-Breathing Organ |
| ABRAVAS | Associato Brasileira de Veterinarios de Animais Selvagens ( Brazilian Small Animal Veterinary Association) |
| ABRAVAS | Associato BRAsileira de Veterinarios de Animais Selvagens (Brazilian Small Animal Veterinary Association) |
| ABRS | Association of British Riding Schools |
| ABS | American Breeder Service |
| ABS | Animal Behavior Society |
| ABSA | American Biological Safety Association |
| ABU | Artificial Breeding Unit |
| ABUP | Animal Breeding Upgrading Program |
| ABVA | Association of British Veterinary Acupuncturists |
| ABVP | American Board of Veterinary Practitioners |
| ABVR | American Board Of Veterinary Radiology |
| ABVS | American Board of Veterinary Specialties |
| ABVT | American Board of Veterinary Toxicology |
| AB-WRSA | American Branch - World Rabbit Science Association |
| AC | Abandoned Cat |
| AC | Alley Cat |
| AC | Attack Cat |