| AAPP | American Academy on Physician and Patient |
|---|---|
| AAPPO | American Association of Preferred Provider Organizations |
| AAPS | American Association of Plastic Surgeons; Arizona Articulation Proficiency Scale; Association of American Physicians and Surgeons |
| AAR | active avoidance reaction; acute articular rheumatism; antigen-antiglobulin reaction |
| aar | against all risks |
| AARE | automobile accident, rear end |
| AAROM | active assertive range of motion; active-assisted range of motion |
| AARP | American Association of Retired Persons |
| AART | American Association for Rehabilitation Therapy; American Association for Respiratory Therapy |
| AAS | Aarskog-Scott [syndrome]; acid aspiration syndrome; alcoholic abstinence syndrome; American Academy of Sanitarians; American Analgesia Society; aneurysm of atrial septum; anthrax antiserum; aortic arch syndrome; atomic absorption spectrophotometry |