| Acronym | Definition |
|---|
| AAR➣Against All Risks |
| AAR➣American Academy of Religion |
| AAR➣Association of American Railroads |
| AAR➣All-American Rejects (band) |
| AAR➣After Action Report |
| AAR➣After Action Review |
| AAR➣Adobe Acrobat Reader (Adobe Systems, Inc.) |
| AAR➣Aircraft Accident Report |
| AAR➣Archives Audiovisuelles de la Recherche (French: Audiovisual Research Archives) |
| AAR➣Annual Activity Report (various organizations) |
| AAR➣Android Archive (mobile application files) |
| AAR➣Air America Radio (talk radio network) |
| AAR➣Alabama Association of Realtors (Montgomery, AL) |
| AAR➣Allens Arthur Robinson (law firm; Australia) |
| AAR➣Agent Architecture |
| AAR➣Autodesk Authorized Reseller |
| AAR➣Automatic Alternative Route |
| AAR➣Automatic Acronym Retrieval |
| AAR➣Adobe Acrobat Reader |
| AAR➣Automatic Air Recirculation |
| AAR➣At Any Rate |
| AAR➣American Association of Railroads |
| AAR➣American Academy in Rome |
| AAR➣Army Armament Research (US Army) |
| AAR➣Apple Authorized Reseller |
| AAR➣Automated Aerial Refueling (US NASA) |
| AAR➣Association of Amercian Railways |
| AAR➣Association for Aid and Relief (Tokyo, Japan) |
| AAR➣All American Racers |
| AAR➣Arcadia Association of Realtors (Arcadia, CA) |
| AAR➣Alkali-Aggregate Reaction |
| AAR➣Approved Auto Repair (American Automobile Association) |
| AAR➣Age-Adjusted Rate (health statistics) |
| AAR➣Air-to-Air Refueling |
| AAR➣Authority for Advance Rulings (India) |
| AAR➣Antigen-Antikörper Reaktion (German: Antigen-Antibody Reaction) |
| AAR➣Automatic Alternate Routing |
| AAR➣Association of Authors' Representatives, Inc. |
| AAR➣Adult Abuse Registry (Delaware) |
| AAR➣Average Annual Rainfall |
| AAR➣Accumulation-Area Ratio |
| AAR➣Alliance for Aging Research |
| AAR➣Allen Aircraft Radio (est. 1951; Wood Dale, IL) |
| AAR➣Action for Aboriginal Rights |
| AAR➣Association for Automated Reasoning |
| AAR➣Airport Acceptance Rate |
| AAR➣Astronomy and Astrophysics Review (Springer publication) |
| AAR➣Association to Aid Refugees (Japan) |
| AAR➣Aarhus, Denmark - Tirstrup (Airport Code) |
| AAR➣Airport Arrival Rate (capacity measure) |
| AAR➣Active Array Radar |
| AAR➣Administrative Adjustment Report |
| AAR➣Antigen-Antibody Reaction |
| AAR➣Alliance des Associations de Retraités (French: Alliance of Pensioners' Associations; Quebec, Canada) |
| AAR➣Automatic Address Recognition (various businesses) |
| AAR➣American Association of Religion |
| AAR➣Alfa, Access and Renova (Russian Oil Co) |
| AAR➣Aortic Aneurysm Repair |
| AAR➣Air to Air Receive |
| AAR➣Air Augmented Rocket |
| AAR➣Antigen-Antiglobulin Reaction |
| AAR➣Affirmative Action Representative |
| AAR➣Airworthiness Assurance Research and Development Branch (US FAA) |
| AAR➣Automatic Adaptive Routing |
| AAR➣Asiana Airlines Republic of Korea (ICAO code) |
| AAR➣Atlas of Australian Resources |
| AAR➣Army Area Representative |
| AAR➣Adaptive Auto-Regressive |
| AAR➣Acoustic Assessment Report |
| AAR➣Action Aid Rwanda |
| AAR➣Arrival and Assembly Railroads |
| AAR➣Aktiebolaget Atomenergi Research |
| AAR➣Agriculture Acquisition Regulation (US Department of Agriculture) |
| AAR➣Airborne Allergen Report |
| AAR➣Army Achievement Award |
| AAR➣Automatic Answering and Recording |
| AAR➣Audit Agenda Record |
| AAR➣Ask Another Race |
| AAR➣Agence Architecture Rey (French architecture agency) |
| AAR➣Authorized Area Representative |
| AAR➣Auto Analysis Stage (Infrared Space Observatory data analysis) |
| AAR➣Aveize Auto Rétro (car club; France) |
| AAR➣Area Access Rate |
Aar - a river in north central Switzerland that runs northeast into the Rhine