| Abbreviations | Meaning |
 | AAP | Association Of Academic Physiatrists |
 | AAP | Association Of American Physicians |
 | AAPA | American Academy Of Physician Assistants; American Association Of Pathologist Assistants |
 | AAPB | American Association Of Pathologists And Bacteriologists |
 | AAPCC | American Association Of Poison Control Centers |
 | AAPHD | American Association Of Public Health Dentists |
 | AAPHP | American Association Of Public Health Physicians |
 | AAPL | American Academy Of Psychiatry And The Law |
 | AAPM | American Association Of Physicists In Medicine |
 | AAPM&R | American Academy Of Physical Medicine And Rehabilitation |
 | AAPP | American Academy On Physician And Patient |
 | AAPPO | American Association Of Preferred Provider Organizations |
 | AAPS | American Association Of Pharmaceutical Scientists |
 | AAPS | American Association Of Plastic Surgeons |
 | AAPS | Association Of American Physicians And Surgeons |
 | AARC | American Association For Respiratory Care |
 | AARP | American Association Of Retired Persons |
 | AART | American Association For Rehabilitation Therapy; American Association For Respiratory Therapy |
 | AAS | American Analgesia Society |
 | AAS | Aarskog-Scott [syndrome]; Acid Aspiration Syndrome; Alcoholic Abstinence Syndrome; American Academy Of Sanitarians |
 | AASD | American Academy Of Stress Disorders |
 | AASH | Adrenal Androgen Stimulating Hormone; American Association For The Study Of Headache |
 | AASP | Acute Atrophic Spinal Paralysis; American Association Of Senior Physicians; Ascending Aorta Synchronized Pulsation |
 | AASS | American Association For Social Security |
 | AAST | American Association For The Surgery Of Trauma |
 | AATB | American Association Of Tissue Banks |
 | AATS | American Association For Thoracic Surgery |
 | AAVMC | Association Of American Veterinary Medical Colleges |
 | AAVP | American Association Of Veterinary Parasitologists |
 | ABA | Abscissic Acid; Allergic Bronchopulmonary Aspergillosis; American Board Of Anesthesiologists |
 | ABA | American Burn Association; Antibacterial Activity; Arrest Before Arrival; Autonomic Blocking Agent |
 | ABAT | American Board Of Applied Toxicology |
 | ABB | Albright-Butler-Bloomberg [syndrome]; American Board Of Bioanalysis |
 | ABCN | American Board Of Clinical Neuropsychology |
 | ABDPH | American Board Of Dental Public Health |
 | ABE | Acute Bacterial Endocarditis; American Board Of Endodontics; Botulism Equine Trivalent Antitoxin |
 | ABEM | American Board Of Emergency Medicine |
 | ABEPP | American Board Of Examiners In Professional Psychology |
 | ABGC | American Board Of Genetic Counseling |
 | ABIM | American Board Of Internal Medicine |
 | ABIMCE | American Board Of Internal Medicine Certifying Examination |
 | ABMG | American Board Of Medical Genetics |
 | ABMM | American Board Of Medical Management |
 | ABMS | American Board Of Medical Specialties |
 | ABMT | American Board Of Medical Toxicology; Autologous Bone Marrow Transplantation |
 | ABO | American Board Of Orthodontists |
 | ABOHN | American Board For Occupational Health Nurses |
 | ABOMS | American Board Of Oral And Maxillofacial Surgery |
 | ABOP | American Board Of Oral Pathology |
 | ABOS | American Board Of Orthopaedic Surgery |