| Acronym | Definition |
|---|
| AR | Argentina |
| AR | Arkansas (US postal abbreviation) |
| AR | Assault Rifle |
| AR | Argon |
| AR | Accounts Receivable |
| AR | Arabic |
| AR | Administrative Record |
| AR | Army Regulation |
| AR | Amateur Radio |
| AR | Annual Report |
| AR | Accelerated Reader |
| AR | Adventure Racing |
| AR | Animal Rights |
| AR | Army Reserve |
| AR | As Required |
| AR | Annual Reviews |
| AR | Action Required |
| AR | American Revolution |
| AR | Action Replay (game console cheat device) |
| AR | Active Region (sunspot observation) |
| AR | American Racing (American Racing wheels) |
| AR | Action Research |
| AR | Air Rifle |
| AR | Annual Rate |
| AR | Access Router |
| AR | Amazing Race (reality TV show) |
| AR | Acrobat Reader (Adobe Systems) |
| AR | Armor |
| AR | Anti-Reflection |
| AR | Automatic Rifle |
| AR | Abuse Report (gaming, Second Life) |
| AR | Augmented Reality |
| AR | Anti-Reflective |
| AR | Aspect Ratio |
| AR | Acoustic Research (loudspeaker manufacturer) |
| AR | Authorized Representative |
| AR | Annual Return |
| AR | After Rebate |
| AR | Abbey Road (Beatles album/song) |
| AR | Aromatic |
| AR | Androgen Receptor |
| AR | Argent (Heraldic White or Silver) |
| AR | Action Report |
| AR | Arizona Republic (newspaper) |
| AR | Activity Reports |
| AR | Antibiotic Resistance |
| AR | Account Representative (Sprint) |
| AR | Repair Ship |
| AR | Aishwarya Rai (Indian actress) |
| AR | Abnormal Returns |
| AR | Ayn Rand (novelist and philosopher) |
| AR | Authorized Reseller |
| AR | Armalite (rifle company) |
| AR | All Risks |
| AR | Aerolíneas Argentinas |
| AR | Association Rules |
| AR | Atlantic Records (record label) |
| AR | Address Register |
| AR | Autoregressive |
| AR | Alternate Routing |
| AR | Appenzell Außerrhoden (Swiss Half Canton) |
| AR | Allergic Rhinitis |
| AR | Alan Rickman (British actor) |
| AR | Autosomal Recessive (genetics; recessive gene on one of the 23 pairs of autosomes) |
| AR | Assembleia da República (Portuguese parliament) |
| AR | Arrêté Royal (French: Royal Decree; Belgium) |
| AR | Adverse Reaction |
| AR | Accusé de Réception (French: Acknowledgment of Receipt; mail) |
| AR | Artificial Respiration (aka artificial resuscitation) |
| AR | Antimicrobial Resistance |
| AR | Atmospheric Research |
| AR | Ancien Regime (gaming) |
| AR | Adrenaline Rush (gaming; also an IMAX film) |
| AR | Arsenide |
| AR | Acknowledge Receipt |
| AR | Air Route |
| AR | Air Refueling |
| AR | Army Ranger |
| AR | Aortic Regurgitation (aortic insufficiency) |
| AR | Anal Retentive |
| AR | Air Resistance |
| AR | Area Ratio |
| AR | Arista Records (record label) |
| AR | Attributable Risk |
| AR | Appenzell Ausser-Rhoden (postcode, Switzerland) |
| AR | Aldose Reductase |
| AR | Acute Rejection |
| AR | Aerial Refueling |
| AR | American Robin |
| AR | Angle Resolved |
| AR | All Rail |
| AR | Attrition Rate |
| AR | Access Right |
| AR | Abandon Rate |
| AR | Arm's Reach |
| AR | Arezzo, Toscana (Italian province) |
| AR | Authorization Request |
| AR | Anti-Radiation |
| AR | Aqua Regia |
| AR | Aerial Reconnaissance |
| AR | Agency Resources |
| AR | Arrest Report (law enforcement) |
| AR | Attack Rating (Diablo II) |
| AR | Acquisition Reform |
| AR | Autonomous Republic |
| AR | Access Rate |
| AR | Assistant Registrar |
| AR | Automatic Response |
| AR | Area Representative |
| AR | Avis de Réception (Canada Post) |
| AR | Age Regression |
| AR | African Rights |
| AR | Anti-Radar |
| AR | Atrophic Rhinitis (pig respiratory disease) |
| AR | Axial Ratio |
| AR | Ancestral Roots (genealogy) |
| AR | Approval Request |
| AR | Air Reconnaissance |
| AR | Active Radar |
| AR | Activity Ratio |
| AR | Approximate Reasoning |
| AR | Attack Release |
| AR | Anton Rubinstein (classical pianist) |
| AR | Auto Redial |
| AR | Analytical Reagent |
| AR | Airborne Reconnaissance |
| AR | Aftermath Records (record label) |
| AR | Agent Report |
| AR | Add Register |
| AR | Abstellraum (German: storage room) |
| AR | Acceptance Review |
| AR | Asistencia Respiratoria |
| AR | Acquisition Risk |
| AR | Art Remains (online art gallery) |
| AR | Affiliate Relations |
| AR | Accounts Register |
| AR | Acquiescence Ruling |
| AR | Application Record |
| AR | Automation Resources |
| AR | Automatic Recall (Bellcore) |
| AR | Acetal Resin |
| AR | Arrezo (postcode, Italy) |
| AR | Advanced Reactor |
| AR | Acoustic Reflex |
| AR | Alarm Reaction |
| AR | Administrative Requirement |
| AR | Assessment Request |
| AR | American Rifleman Magazine |
| AR | Armor Rating (gaming, Asheron's Call 2) |
| AR | Auxiliary Relay |
| AR | Acquisition Request |
| AR | Alabama Railroad |
| AR | Alarm Report |
| AR | Approved Rejected |
| AR | Air Revitalization |
| AR | Asset Reconciliation |
| AR | Anomaly Report |
| AR | Application Requester |
| AR | Artificial Resuscitation |
| AR | Auburn Reporter (community newspaper) |
| AR | Anti-Reflectance |
| AR | Arise Records |
| AR | Airworthiness Representative |
| AR | Airborne Relay |
| AR | Activity Resume (ITU-T) |
| AR | American Rivers, Inc. |
| AR | Advice of Receipt (Canada Post) |
| AR | Absorber Rod |
| AR | Acoustique Renforcée (French: Enhanced Acoustics; window noise insulation) |
| AR | Auxiliary Room |
| AR | Archival Researcher |
| AR | Affirmative Rebuttal (debate) |
| AR | Postal Fiscal (Scott Catalogue prefix; philately) |
| AR | Attrition Reserve (aircraft) |
| AR | Atmospheric Revitalization |
| AR | Automatic Resupply |
| AR | Auxiliary Receiver |
| AR | Avance-Retard (French) |
| AR | Auscultacion Respiratoria (Spanish: Respiratory Auscultation) |
| AR | Arrow Revolver (game, Mabinogi) |
| AR | Attributive Risk |
| AR | Allied Racing (Halo racing clan) |
| AR | ASR Status |
| AR | Armor Rendering (gaming, Asheron's Call) |
| AR | Argonne Area Office (US DOE) |
| AR | Altesse Royal (French: Royal Highness) |
| AR | Aeronautical Requirement |
| AR | Adaptive Reception Control |
| AR | Architecture and Requirements Office (NIMA) |
| AR | Automation Recall |
| AR | Amusement Radio (online radio station) |
| AR | Anno Resurrectionis (Year of the Resurrection, epigraphy) |
| AR | Agonist Reversal (PNF technique) |
| AR | End of message / Out (logging abbreviation) |
| AR | Allotment Reconciliation |
| AR | Agent Requisitions |
| AR | As Removed (avionics) |
| AR | Adrenergic Receptor (protein) |
| AR | Akademia Rolnicza (Polish: University of Agriculture) |
| AR | Assistant Referee (sports) |